U0101: Top reason is almost always a loose connector on the TCM 99% of the time!!! This bulky connector sits vertically on the TCM thus loosening with time between the cable harness and the TCM. Inspect, clean and secure the connection is one of the best first steps ever.
Explaining the how you broke down the diagnostic process is a big help. But like Smitty below, as soon as I'm staring at an issue, I forget every video I watched. Like Scannerdanner says, you have to have time in the field to be proficient. Thank you doing these videos. I always enjoy your lessons Mike.
Hey Wyatt, thanks man! It doesn't help getting called off a network diag to do 2 waiter oil changes either. I don't miss those days. I love working at my own pace in my own shop. Though I may get called away for a crying baby at this point, that's few and far between compared to those 4:00pm waiters on a Friday haha! Mike Becker, Senior Instructor
4 channel both ecu's, perfect. Learn tons from your channel, and today it's easier and faster to communicate and learn than 1993 when I was just starting out on vehicles professionally. Thanks to all the professional instructors out there paying their dues and passing it on. Thank you!
Had exact same, identical problem many years ago, on same 07 mazda 3. My first dealing with can bus communication, ( like a lost child with my vantage 2500) replacing the tcm got the car out of the shop, but thanks to your video, I'm skeptical that it was maybe, just maybe a connection issue....thanks again for another education.
Hey Gunnar, thanks for watching! Weird how many CAN issues i've heard of now on that Mazda 3. I didn't realize how common of an issue it actually was. Mike Becker, Senior Instructor
That's how we learn. You found it and you fixed it. As long as there are small pins like that one, with very small currents and signals running through them, pin fitment will be a problem after many years and miles.
Hey Mike, exactly. Every time that connector is removed it weakens the pin fitment as well. Who knows how many times it was taken off prior to me seeing it! Mike Becker, Senior Instructor
And it probably didn't need a TCM in the first place. Like I always say it's always something stupid. Most times we never get the whole story from the customer. Thanks for the video!
Hey Matt, maybe it did, maybe it didn't...impossible to know now. Personally, I wonder if it did need the TCM, it was replaced accurately, but the testing/unplugging/plugging in multiple times somehow ruined the connector. A main connector like that isn't intended to come apart very many times. When I was at factory training for KIA we we're told 3 times...crazy! Mike Becker, Senior Instructor
GoTech yeah when I worked at GM dealer I would’ve replaced the 2 pins for the CAN and repaired it that way. Only 2 wires instead of 20. I like your use of the scope as well. Good stuff.
Thanks Matt! I did have to add in the cruise control wiring for the new (used) connector. The Mazda connectors kind of suck to take apart! Mike Becker, Senior Instructor
Great advice fixed my problems IV been battling everything from pcm tcm wire harness I pulled every wire out didn't find no breaks in wres seen your video did probe test with a needle that was right size as pin found my bad female plugs thanks I've spent lots money time if only I seen this video first 😂
I feel your pain , I once spent nearly 8 hours going through a wiring loom only to find a very thin wire which had broken and had the greenies. 5 mins of soldering then an hour of reassembly 😖😖😖😖😖😖. The owner had paid three other shops good money to fix it, but he only wanted to pay me for the soldering.....I was losing the will to live
Hey Mazdaman, I hope you were able to convince the owner to pay accordingly for the service he received. I also hope that it earned you a customer for life. A lot of times situations like this are great for that! Mike Becker, Senior Instructor
@@GoTechTraining Yes it all worked out really well he realised that he had been ripped off and had parts he did not need, although I'm semi retired now still do his company vans , his and his wifes cars and the kids and other members of the family for over 20 years. They are all friends now like most of my old customers. I put it down to I'm a straight talking person I say what the problem is what needs to be done and how to avoid it in the future. If it's been driven by an idiot I will say so, and 99.9% of the time someone will say yes... If the job is a quick fix like bulbs , wipers or a puncture repair I charge nothing. The goodwill generated and then told to others has bought me so many customers. Main dealers would never do that.
@@GoTechTraining My problem with this type of diag is getting the service writer to understand my time it worth charging for. They don't believe i should get paid for hours taken and won't even try to sell the time. The old "we'll get you on the next one". OK? Seems to me i'm still losing...but I retired in April. They can stuff it.
Thanks Rafael! Yeh, for sure. Rarely do the electronics fail on their own...more often they are killed by something else. Mike Becker, Senior Instructor
Having similar issues with my 2020 malibu rs....chevy can't even figure it out and its under warranty still. To the shop 3 times almost 2 months later still has not neen resolved. Great video !!
@GoTech Mike, I've run into that kind of problem, with my own car, a 2004 Dodge Neon R/T, with a cam sensor issue. Kept getting the P0340 code, checked the wiring and replaced the sensor. Later figured out that the problem was the tabs inside the pins in the connector. The tabs had spread, causing an intermittent contact issue. It didn't help that the wiring harness was moving when the engine moved under acceleration. I simply pushed the tabs back in, fixed the issue for good, That was a few years ago. Have not had any cam sensor issues since. It is likely the same issue with this issue, and why the pin feels loose when the backprobe pin was inserted. Another issue that i've found is that sometimes the pin will not be inserted all the way into the connector so that it gets locked in, and that causes issues like this. When the backprobe pin was inserted, it pushed the pin in far enough to lock it in and make better contact with the other side.
Check the connector before taking the harness apart, on the basis of looking for the easy things first. Plus, the connector is going to be 1000x as likely as the splice since it's a lot more mechanically complicated. If both sides of the connector have a pigtail you can often test continuity through the connector which helps too
Deja Vu. Our shop encountered this exact same problem on this exact same vehicle. All testing was initially done using the "back probing" method but every test showed no problem. To make matters worse, it was an intermittent problem. It would work great for a while then error out. I made the call that it must be an intermittent bad TCM, replaced the module, and the car drove fine ... for a while, then the issue returned (yes ... I ate the cost of a TCM). We switched to the "vampire tap" method for continued testing and that's when we found the problem. We were not able to find a used connector and had to replace the engine harness.
Hey Darryl, ahh the "vampire tap" I like that. I may use that in the future! Crazy that it was the same car, same issue...wonder if it's common on these!? I ended up with an "EBAY" used connector. Seems to have done the job though. Mike Becker, Senior Instructor
Whoa, replacing whole connector pigtails or harnesses from one bad terminal? Can you not find the connector/terminal type, then simply depin the problem circuits, cut off the old terminal and crimp a replacement on?
@@Turbochargedtwelve A lot of these circuits are now using 22ga wiring. They are very difficult to achieve a solid connection especially if the harness can't be pulled up to get access to allow crimpers in. But this situation also brings up another consideration. Lots of instructors preach about not touching/moving anything around because it might temporarily "fix" the problem. I disagree with that. l still do wiggle/tap tests like Ford rec back 30 years ago.
Gail Taylor I haven’t seen that yet, but I work professionally on heavy automotive stuff (class 6,7,8) or personally on stiff no younger than five years old. Still, using 22ga wire only means that you need to find the correct size terminals and tooling for them. Every time you move a component you open yourself up to more liability and yes I agree packaging is super tight on most components. Getting the connector loose especially on high pin count ones like the major modules can be a real challenge and is often not as delicate as you’d prefer. Worst case scenario you do end up right where he did, needing to replace the whole harness, or at the least the whole pigtail. It is sad that policies now would rather get the vehicle back out the door quickly at the cost of expense and quality
I deal with many 5 vdc connectors similar to that in late model domestic refrigeration and MANY times have found an invisible micro-corrosion has occurred. It can throw off a 2-5 kilo ohm sensor to alter a compartments temperature wherever the sensor is in control . Slightly feeezing or not cold enough, and in certain environments, unshielded and unprotected connections will cause a 12vdc fan motor or baffle actuator to stall. It is uncommon for those components to be the problem, but if you do not test anything and blindly replace the part, the action of disconnecting and reconnecting that will certainly make it look as if was correctly diagnosed since the connection was refreshed from the reassembly act. I usually dry fu-xk the connector a half dozen times and tweak both members of that union, and maybe use electricians tape to create a barrier, and that will buy it a few or more years. Almost never happens on the line voltage connectors. And it's usually the N side of the DC circuit .
Amazing video it really helps to know what probably going to be done at the auto electricians in town with my ve commodore to find the problem I have with a pending U0100/P0700 fault codes
I had one years ago on a 1982 Mitsubishi Lancer Turbo. This car was an ex Rally car and the owner complained that he could not get it to start. We rigged a bypass so he could get the fuel pump to work. At the weekend we later discovered that the fuel supply connector at the ECU had drifted back away from proper contact with the pin. Turns out he had been swapping ECUs just before it got its problems. Nowadays at my age I always use a bright light and magnifying glass to inspect the ECU plugs.
Hey Bigcliffe, when I was at factory training for KIA, they told us the ECU connector is only intended to come apart 3 times. Any more than that and it should be replaced. Crazy but it makes sense! Mike Becker, Senior Instructor
@@GoTechTraining Now that is interesting.My brother had a 1986 Mitsubishi Mirage Turbo that we spent lots of time and money on to get that car to do a 13.8 second 1/4 mile time. The problem was that the wire harness was the weak point of that car. The heat of the turbo and the high under bonnet temperatures made me think that there should have been available as a spare a full engine to ECU harness.
Nice find, Mike! I don't get many jobs like this, so on the rare occasion I do, I find myself fumbling like a rookie and wasting more time than I care to admit. 45 minutes ain't bad in my world, LOL - I bet I'd quadruple that! No matter how many vids I watch on this, I seem to forget everything as soon as the vehicle is in front of me, lol. It's like stage fright! I'll get it one of these days! My 10 year plan, HAHAHA! Great stuff as usual man. 👍🍻
Hey Smitty, it's rare I get comm issues too. I enjoy working on them because I always learn something in each case. That's what it's all about. Learn something on every single one and eventually it'll be easy haha! Mike Becker, Senior Instructor
Personally when dealing with a problem like this I try to have some one monitoring data communications on the scanner when I even have to move a wire just in case comms comes back. Have run into connection problems like this many times in the past 40 years. One of the reasons I warn customers about the perils of intermittent connections and the possibility it may temporally fix it's self and remain so for a long time.
Hey Ram50v8, that's a good process. Unfortunately, i'm all by myself when I work on stuff at home. Interestingly enough, I did do a traditional wiggle test on the harness and had no change. Nothing changed until I back probed the connector the 2nd time with the jumper lead. Mike Becker, Senior Instructor
@@GoTechTraining Mike, I get all the interesting problems sent to my shop that no one can figure out. Like a tail light bulb I found that was causing an intermittent transmission shifting issue. Or a car that was having intermittent multiple systems failures only when the husband drove and the dealer could not find it after multiple attempts. And hundreds more
Sounds like you're the guy to see in your town. Good for you, a reputation like that doesn't happen overnight! Tail light causing transmission shifting issues sounds like a fun one. Something back feeding power? Mike Becker, Senior Instructor
@@GoTechTraining You'll get a chuckle out of this one. It was a case of customer installed LED bulbs and 5 of 30 the leds in the left light would flicker at a high rate causing noise in the system.
Hey Bogart Bacus, pin tension issues can be the worst to diag...especially the incredibly intermittent ones. Ugh, the headaches, right!? Mike Becker, Senior Instructor
Hey Mike so What was you recommendation for repair? To Replace the whole harness, Connector, or remove that one pin and repair it. If you do pin level repair can you please make a video on that
Hey Cooking With KJ, any of those would be approved methods of repair. The pin repair on this connector would be very tricky, tiny pins...The customer chose to have the entire connector replaced. He chose a used connector to have installed. Mike Becker, Senior Instructor
nice video, thanks! what program did you use to get the wiring diagram-I like the way you were able to clear everything out except what you really wanted to look at-made it very clear then!
where are you located I like how you go about in doing diagnosis on the vehicles I got a vehicle where nobody can find why is burning too much fuel I was wondering if you can tackle that job
Great tips; you quickly narrowed down where the problem had to be, and you learned a lesson about checking the integrity of the actual connection instead of relying on back probing, which takes the actual problematic, low-socket-tension connection out of the tested circuit. If you had started by popping the white cover off of the sockets, you may have been able to spot the loose female connector by visual inspection before back probing that circuit and using new wires to go around the possible problem areas you had quickly identified. Thanks for making this video. I have a similar problem I am getting ready to dig into today, and the sharing of what you learned is extraordinarily helpful to me.
Hey, Mike. I am not really familiar with the CAN Network. I was hoping one day that you would do a lecture on. My main issue is the can controller and the can transceiver. Is the can transceiver incorporated in the can controller? Should I expect a communication code with a bad transceiver? I am expecting the answer to be no, because they always tell you to disconnect modules to find the one(s) with the bad transceiver(s), but I may be wrong. Your answer would be greatly appreciated!
Hey Carlos, networking is far from my specialty. I do hope to do a class on it at some point. I have some studying to do before then though. Mike Becker, Senior Instructor
Always love pin fitment issues, they can drive you nuts. Most of the ones I get are intermittent to the point they happen once a year. Enough to make you want to start drinking..
Had many issues with this problems,some cars are flood cars that were fixed by replacing modules and fuse boxes,which fixed the issue,but many yrs later we end up trying to figure out this issues,not knowing it was a flood car four yrs ago ,creating many pins to corrosion.
Thanks alot for the video Mike. So i am right i thinking when you first hooked up to the PCM and TCM lines you used piercers on all 4 wires and then just to install the jumper you back probed yes? Thanks Dave
Hey David, my intial scope capture that showed the "bad" blue trace was back probed at the connector. I then removed that back probe and put my jumper wire in. The second back probing is what "fixed" my issue. Mike Becker, Senior Instructor
Ok Mike thanks for clearing that up. I just saw the 2 piercing tools on your screenshot and thought you might have originally pierced all 4 and then just back probed the jumper. Just wanted to get it clear in my head, thanks again
Yes Thank you for the indepth quick video. Now to fix my $700+ dealership diagnose with already computer flash for the ecm. I didn't think to ask will that fix the problem for my u1000. But now u1000&u1001 are friends. How in the future to fix it....
U said u were working on a wisconsin vehicle. Are u located in wisconsin. I am looking for some one that can trouble shoot the electrical. If not can u recommend some one. I prefer not to be the guy that just starts replacing things. I already have 1500 into it. Mechanic said we just have to start replacing parts. Had 2 different places lookk at it. Any help would be appreciated.
Hello Beth Grabow, yes we are located in Fond du lac, Wisconsin. If you'd like, we can continue this conversation via email so it stays private. You can reach me at michael.becker@gotech.com Thanks, MIke
Had a Cadillac cts abs com issue. Eventually found the blue slide in wire retainer in the connector was broken and allowing the wire to back out when installed. No room to properly check connector. Only found the problem when i disassembled the connector in desperation!
Good day i am talking to from trinidad and tobago my problem is that my mazda 3 keep going into forth gear while driving for it to go back to drive i have to take it off the engine and put it back on again for it to drive nomal again
I fixed a similar Mazda my buddy a mechanic replaced with new tcm, and still didn't work checked for tcm power signal with my autell no power did connector wiggle test power came on removed plug retighned terminal was fixed
Great video Mike! One question..How did probe to capture the bad waveform? You mentioned at the tcm connector, but I’m kinda confused. Wouldn’t back probing show a good waveform even if there is no contact between male and female pins?
Hey OC Diagnostics, my initial back-probing that captured the bad waveform was a bad connection on the back side of female pin. So, if I had a good connection then yes, it would have shown a good waveform. Mike Becker, Senior Instructor
At least you double-checked your work before returning it to the customer. As the saying goes, "Measure twice, cut once." That's still better than tossing a TCM at it for nothing like the customer did in the first place.
Hey Joseph, thanks for watching! It's funny, when working on cars I always apply that...woodworking...ugh let's just say I have a lot of waste, haha! Mike Becker, Senior Instructor
Hey J. Angus, I would have pierced the wires and seen that I had communication reaching the TCM connector. I would have then checked power and ground to the TCM. Comm, power and ground would have lead me to thinking it was a TCM issue, but I always verify pin tension prior to ordering a module...so I would have found it then. No need to tear the harness apart like I did. Mike Becker, Senior Instructor
Hi Mike. Thank you for another great vid. Unrelated question; Around here, we have NAPA, Aotozone, Pep Boys and Advance Auto. All of their products are in their own packaging. Where can I get your products (preferably with your packaging)? I don't see them locally.
Hey P Sav, thanks! Many of our products come in those store branded packages. There are some places you can buy stuff in a Wells or WVE box, but its not as easy to come by as the big stores. If you're ever looking for a part and want it to be ours, give our techline a call. They can tell you where you can buy it. Mike Becker, Senior Instructor
I currently have this U0101 code on my 2014 Chevy Malibu. When the TCM is down, the car is stuck in third gear (limp mode) and gear shift is not illuminated. When I drive 20-30 minutes in limp mode , the TCM does come back and stays as long as I keep driving. When I shut the engine off and wait about 10 minutes and turn engine back on, the TCM fails again, so it's an intermittent issue. Chevy dealership has no answers after I paid them 224 dollars in diagnostic fees. They wanted an additional $1300 to further diagnose it and obviously I declined that, so now I'm stuck with a TCM that goes in and out. Very frustrating. I have taken that TCM connector off and on so many times that I've lost count. Nothing is working.
Same thing happened when I was running parameter diagnostics on my TCM and T/C my Jeep was making a lot of loud noises from relays. Got better after a few restarts
@gotech. My transmission is stuck in limp mode and responds slowly in reverse to 80% pedal pressure. only DTC U0101; U0402. It's TORQUE FLITE 8HP70 transmission. I can't believe my transmission has failed at 40934 mi.
I can’t even locate TCM on the car I’m working on (2011 Altima Hybrid) . Identifix illustration is different. Very frustrating. Most thing I hate about electrical is figuring out which wire is which.
Do you have a website to show exactly pictures what you did because I have sent my tcm back to many times (all Computer repair parts). I just got it back and it's still acking up
I have a similar issue with my mazda 3 2005 2.3. It jumps when goes into second gear when engine still cold mostly . Could this be the TCM as well or wiring or conector ?
Hey man I have a 2007 Mazda 3 and the TCS light comes on as well as the check engine and when I put the car into drive it goes into 3rd gear and when I pass reverse it gives the car a really rough shape and same when I put it into reverse. I’ve replaced the map censor within the car in hopes it would bring the car out of limp mode. Turned the car on after I replaced the map censor and it went into first gear and reverse fine without the rough shake to the car. Went back the next day and it’s doing the same thing. Not sure if it’s because of my connection to the TCM that would be my next guess from watching your video. Any suggestions before I check the TCM?
How did you fix it??
Hey Don, I replaced the entire TCM connector with a used one. Solder and heat-shrink was used to connect each wire.
Mike Becker, Senior Instructor
Jam the jumper wire in the tcm until you get commication, close the hood and call the customer.
*pray it doesnt turn into a come back*
@@johnsko3321 how much did the repair cost ?
@@GoTechTraining that's a lot of work.
@@GoTechTraining wow your moitivated I would of just depinned and repin the can wires.
U0101: Top reason is almost always a loose connector on the TCM 99% of the time!!! This bulky connector sits vertically on the TCM thus loosening with time between the cable harness and the TCM. Inspect, clean and secure the connection is one of the best first steps ever.
Explaining the how you broke down the diagnostic process is a big help. But like Smitty below, as soon as I'm staring at an issue, I forget every video I watched. Like Scannerdanner says, you have to have time in the field to be proficient. Thank you doing these videos. I always enjoy your lessons Mike.
Hey Wyatt, thanks man! It doesn't help getting called off a network diag to do 2 waiter oil changes either. I don't miss those days. I love working at my own pace in my own shop. Though I may get called away for a crying baby at this point, that's few and far between compared to those 4:00pm waiters on a Friday haha!
Mike Becker, Senior Instructor
4 channel both ecu's, perfect. Learn tons from your channel, and today it's easier and faster to communicate and learn than 1993 when I was just starting out on vehicles professionally. Thanks to all the professional instructors out there paying their dues and passing it on. Thank you!
Hey Mark, thanks for watching! It's all about communication :)
Mike Becker, Senior Instructor
Had exact same, identical problem many years ago, on same 07 mazda 3. My first dealing with can bus communication, ( like a lost child with my vantage 2500) replacing the tcm got the car out of the shop, but thanks to your video, I'm skeptical that it was maybe, just maybe a connection issue....thanks again for another education.
Hey Gunnar, thanks for watching! Weird how many CAN issues i've heard of now on that Mazda 3. I didn't realize how common of an issue it actually was.
Mike Becker, Senior Instructor
That's how we learn. You found it and you fixed it. As long as there are small pins like that one, with very small currents and signals running through them, pin fitment will be a problem after many years and miles.
Hey Mike, exactly. Every time that connector is removed it weakens the pin fitment as well. Who knows how many times it was taken off prior to me seeing it!
Mike Becker, Senior Instructor
Watching from philippines. Thank you very much for this technical idea sir. Big salute to you. Its very clear.
Thanks Oto! Hope all is well in the Philippines!
Mike Becker, Senior Instructor
@@GoTechTraining yes sir by the name of the lord. Same too sir mike.
And it probably didn't need a TCM in the first place. Like I always say it's always something stupid. Most times we never get the whole story from the customer. Thanks for the video!
Hey Matt, maybe it did, maybe it didn't...impossible to know now. Personally, I wonder if it did need the TCM, it was replaced accurately, but the testing/unplugging/plugging in multiple times somehow ruined the connector. A main connector like that isn't intended to come apart very many times. When I was at factory training for KIA we we're told 3 times...crazy!
Mike Becker, Senior Instructor
GoTech yeah when I worked at GM dealer I would’ve replaced the 2 pins for the CAN and repaired it that way. Only 2 wires instead of 20. I like your use of the scope as well. Good stuff.
Thanks Matt! I did have to add in the cruise control wiring for the new (used) connector. The Mazda connectors kind of suck to take apart!
Mike Becker, Senior Instructor
Thank you Mike. Have a blessed and safe week to you and your family. Thanks for the redkap shirt info. Got mine today. Nice shirts.
Hey Billy, thanks!!! Glad you like that shirt!
Mike Becker, Senior Instructor
Great advice fixed my problems IV been battling everything from pcm tcm wire harness I pulled every wire out didn't find no breaks in wres seen your video did probe test with a needle that was right size as pin found my bad female plugs thanks I've spent lots money time if only I seen this video first 😂
I feel your pain , I once spent nearly 8 hours going through a wiring loom only to find a very thin wire which had broken and had the greenies. 5 mins of soldering then an hour of reassembly 😖😖😖😖😖😖. The owner had paid three other shops good money to fix it, but he only wanted to pay me for the soldering.....I was losing the will to live
Hey Mazdaman, I hope you were able to convince the owner to pay accordingly for the service he received. I also hope that it earned you a customer for life. A lot of times situations like this are great for that!
Mike Becker, Senior Instructor
@@GoTechTraining Yes it all worked out really well he realised that he had been ripped off and had parts he did not need, although I'm semi retired now still do his company vans , his and his wifes cars and the kids and other members of the family for over 20 years. They are all friends now like most of my old customers. I put it down to I'm a straight talking person I say what the problem is what needs to be done and how to avoid it in the future. If it's been driven by an idiot I will say so, and 99.9% of the time someone will say yes... If the job is a quick fix like bulbs , wipers or a puncture repair I charge nothing. The goodwill generated and then told to others has bought me so many customers. Main dealers would never do that.
@@mazdaman1286 I used to do little things for free and it's amazing how much goodwill that produces, and often referrals to new customers.
@@GoTechTraining My problem with this type of diag is getting the service writer to understand my time it worth charging for. They don't believe i should get paid for hours taken and won't even try to sell the time. The old "we'll get you on the next one". OK? Seems to me i'm still losing...but I retired in April. They can stuff it.
@@gailtaylor1636common problem with the industry, service writers, and money grubbing butt sniffin manager’s
Incredibly helpful for the home diy, really great process of elimination.
Hey N V, thanks for watching! Glad you found the video helpful.
Mike Becker, Senior Instructor
Excellent work. I always look for the mechanical failure in electronics first. They are more prone to fail that the electronics themselves.
Thanks Rafael! Yeh, for sure. Rarely do the electronics fail on their own...more often they are killed by something else.
Mike Becker, Senior Instructor
Having similar issues with my 2020 malibu rs....chevy can't even figure it out and its under warranty still. To the shop 3 times almost 2 months later still has not neen resolved. Great video !!
@GoTech Mike, I've run into that kind of problem, with my own car, a 2004 Dodge Neon R/T, with a cam sensor issue. Kept getting the P0340 code, checked the wiring and replaced the sensor. Later figured out that the problem was the tabs inside the pins in the connector. The tabs had spread, causing an intermittent contact issue. It didn't help that the wiring harness was moving when the engine moved under acceleration. I simply pushed the tabs back in, fixed the issue for good, That was a few years ago. Have not had any cam sensor issues since. It is likely the same issue with this issue, and why the pin feels loose when the backprobe pin was inserted. Another issue that i've found is that sometimes the pin will not be inserted all the way into the connector so that it gets locked in, and that causes issues like this. When the backprobe pin was inserted, it pushed the pin in far enough to lock it in and make better contact with the other side.
Check the connector before taking the harness apart, on the basis of looking for the easy things first. Plus, the connector is going to be 1000x as likely as the splice since it's a lot more mechanically complicated. If both sides of the connector have a pigtail you can often test continuity through the connector which helps too
Thank you Sr.for your time and communication
Thanks for watching Cesar!
Mike Becker, Senior Instructor
Deja Vu. Our shop encountered this exact same problem on this exact same vehicle. All testing was initially done using the "back probing" method but every test showed no problem. To make matters worse, it was an intermittent problem. It would work great for a while then error out.
I made the call that it must be an intermittent bad TCM, replaced the module, and the car drove fine ... for a while, then the issue returned (yes ... I ate the cost of a TCM). We switched to the "vampire tap" method for continued testing and that's when we found the problem. We were not able to find a used connector and had to replace the engine harness.
Hey Darryl, ahh the "vampire tap" I like that. I may use that in the future! Crazy that it was the same car, same issue...wonder if it's common on these!? I ended up with an "EBAY" used connector. Seems to have done the job though.
Mike Becker, Senior Instructor
Whoa, replacing whole connector pigtails or harnesses from one bad terminal?
Can you not find the connector/terminal type, then simply depin the problem circuits, cut off the old terminal and crimp a replacement on?
@@Turbochargedtwelve A lot of these circuits are now using 22ga wiring. They are very difficult to achieve a solid connection especially if the harness can't be pulled up to get access to allow crimpers in. But this situation also brings up another consideration. Lots of instructors preach about not touching/moving anything around because it might temporarily "fix" the problem. I disagree with that. l still do wiggle/tap tests like Ford rec back 30 years ago.
Gail Taylor I haven’t seen that yet, but I work professionally on heavy automotive stuff (class 6,7,8) or personally on stiff no younger than five years old. Still, using 22ga wire only means that you need to find the correct size terminals and tooling for them. Every time you move a component you open yourself up to more liability and yes I agree packaging is super tight on most components. Getting the connector loose especially on high pin count ones like the major modules can be a real challenge and is often not as delicate as you’d prefer. Worst case scenario you do end up right where he did, needing to replace the whole harness, or at the least the whole pigtail. It is sad that policies now would rather get the vehicle back out the door quickly at the cost of expense and quality
I deal with many 5 vdc connectors similar to that in late model domestic refrigeration and MANY times have found an invisible micro-corrosion has occurred. It can throw off a 2-5 kilo ohm sensor to alter a compartments temperature wherever the sensor is in control .
Slightly feeezing or not cold enough, and in certain environments, unshielded and unprotected connections will cause a 12vdc fan motor or baffle actuator to stall. It is uncommon for those components to be the problem, but if you do not test anything and blindly replace the part, the action of disconnecting and reconnecting that will certainly make it look as if was correctly diagnosed since the connection was refreshed from the reassembly act.
I usually dry fu-xk the connector a half dozen times and tweak both members of that union, and maybe use electricians tape to create a barrier, and that will buy it a few or more years.
Almost never happens on the line voltage connectors. And it's usually the N side of the DC circuit .
Great video, and I am hopeful that it will help me fix my Rainier issues.
Amazing video it really helps to know what probably going to be done at the auto electricians in town with my ve commodore to find the problem I have with a pending U0100/P0700 fault codes
I had one years ago on a 1982 Mitsubishi Lancer Turbo. This car was an ex Rally car and the owner complained that he could not get it to start. We rigged a bypass so he could get the fuel pump to work. At the weekend we later discovered that the fuel supply connector at the ECU had drifted back away from proper contact with the pin. Turns out he had been swapping ECUs just before it got its problems. Nowadays at my age I always use a bright light and magnifying glass to inspect the ECU plugs.
Hey Bigcliffe, when I was at factory training for KIA, they told us the ECU connector is only intended to come apart 3 times. Any more than that and it should be replaced. Crazy but it makes sense!
Mike Becker, Senior Instructor
@@GoTechTraining Now that is interesting.My brother had a 1986 Mitsubishi Mirage Turbo that we spent lots of time and money on to get that car to do a 13.8 second 1/4 mile time. The problem was that the wire harness was the weak point of that car. The heat of the turbo and the high under bonnet temperatures made me think that there should have been available as a spare a full engine to ECU harness.
@@GoTechTraining all plugs/outlets have max cycle count which varies widely, 3 seems awfully low though.
Good reminder Mike. Tight is good. Thanks.
Hey Carl, yes a tight fitting terminal connection is ideal!
Mike Becker, Senior Instructor
Nice find, Mike! I don't get many jobs like this, so on the rare occasion I do, I find myself fumbling like a rookie and wasting more time than I care to admit. 45 minutes ain't bad in my world, LOL - I bet I'd quadruple that! No matter how many vids I watch on this, I seem to forget everything as soon as the vehicle is in front of me, lol. It's like stage fright! I'll get it one of these days! My 10 year plan, HAHAHA! Great stuff as usual man. 👍🍻
I feel the same way Smitty!
Hey Smitty, it's rare I get comm issues too. I enjoy working on them because I always learn something in each case. That's what it's all about. Learn something on every single one and eventually it'll be easy haha!
Mike Becker, Senior Instructor
@@GoTechTraining- Very true, Mike!
Hopefully some day it'll all be easy. :)
Personally when dealing with a problem like this I try to have some one monitoring data communications on the scanner when I even have to move a wire just in case comms comes back. Have run into connection problems like this many times in the past 40 years. One of the reasons I warn customers about the perils of intermittent connections and the possibility it may temporally fix it's self and remain so for a long time.
Hey Ram50v8, that's a good process. Unfortunately, i'm all by myself when I work on stuff at home. Interestingly enough, I did do a traditional wiggle test on the harness and had no change. Nothing changed until I back probed the connector the 2nd time with the jumper lead.
Mike Becker, Senior Instructor
@@GoTechTraining Mike, I get all the interesting problems sent to my shop that no one can figure out. Like a tail light bulb I found that was causing an intermittent transmission shifting issue. Or a car that was having intermittent multiple systems failures only when the husband drove and the dealer could not find it after multiple attempts. And hundreds more
Sounds like you're the guy to see in your town. Good for you, a reputation like that doesn't happen overnight! Tail light causing transmission shifting issues sounds like a fun one. Something back feeding power?
Mike Becker, Senior Instructor
@@GoTechTraining You'll get a chuckle out of this one. It was a case of customer installed LED bulbs and 5 of 30 the leds in the left light would flicker at a high rate causing noise in the system.
What kind of program/software do u use that has the wiring diagrams on them?
I've experience a similar issue on Toyota Landcruiser GXR. It was the connector pin of the Transmission.
Hey Bogart Bacus, pin tension issues can be the worst to diag...especially the incredibly intermittent ones. Ugh, the headaches, right!?
Mike Becker, Senior Instructor
Hey Mike so What was you recommendation for repair? To Replace the whole harness, Connector, or remove that one pin and repair it. If you do pin level repair can you please make a video on that
Hey Cooking With KJ, any of those would be approved methods of repair. The pin repair on this connector would be very tricky, tiny pins...The customer chose to have the entire connector replaced. He chose a used connector to have installed.
Mike Becker, Senior Instructor
nice video, thanks! what program did you use to get the wiring diagram-I like the way you were able to clear everything out except what you really wanted to look at-made it very clear then!
Great tip Mike,I’m glad all is well! 👍
Hey Nick, thanks! :)
Mike Becker, Senior Instructor
where are you located I like how you go about in doing diagnosis on the vehicles I got a vehicle where nobody can find why is burning too much fuel I was wondering if you can tackle that job
Hey Braulio, Thanks! I'm located in southeastern WI.
Mike Becker Senior Instructor
Great tips; you quickly narrowed down where the problem had to be, and you learned a lesson about checking the integrity of the actual connection instead of relying on back probing, which takes the actual problematic, low-socket-tension connection out of the tested circuit. If you had started by popping the white cover off of the sockets, you may have been able to spot the loose female connector by visual inspection before back probing that circuit and using new wires to go around the possible problem areas you had quickly identified.
Thanks for making this video. I have a similar problem I am getting ready to dig into today, and the sharing of what you learned is extraordinarily helpful to me.
Thank you, it is great you saved me so much time.
Good video thanks. Did u tighten up the pin sumhow. Or replace the harness as your final fix?
Hey Mark, thanks! This vehicle got a new(used) TCM connector.
Mike Becker, Senior Instructor
Hi, great video. Can you remove the pin and squeeze it lightly with a pliers to add tension or does the pin need to be replaced? Thanks
This is an excellent video my guy, same exact thing happened on my 06
Hey, Mike. I am not really familiar with the CAN Network. I was hoping one day that you would do a lecture on. My main issue is the can controller and the can transceiver. Is the can transceiver incorporated in the can controller? Should I expect a communication code with a bad transceiver? I am expecting the answer to be no, because they always tell you to disconnect modules to find the one(s) with the bad transceiver(s), but I may be wrong. Your answer would be greatly appreciated!
Hey Carlos, networking is far from my specialty. I do hope to do a class on it at some point. I have some studying to do before then though.
Mike Becker, Senior Instructor
GoTech Do you have any other good resources for networking that you recommend?
This was a text book lesson of the birds and the bees. Things got a little frisky there at the end with the connector.
😂🤣😂 After I saw that part, I immediately went to the comments section to look for you. 😃👍🍻
Hahahahah! No better time to practice then now...i'll have to do that for my 2 boys at some point!
Mike Becker, Senior Instructor
Good video thanks!
Any suggestion with lost power steering on subaru crosstreck??
Thank you so much
Great video. Use to hate piercing wires until I ran into same issue
Hey Frank, thanks for watching!
Mike Becker, Senior Instructor
Always love pin fitment issues, they can drive you nuts. Most of the ones I get are intermittent to the point they happen once a year. Enough to make you want to start drinking..
Great video and good lesson to learn, as always I appreciate what you do.
Hey John, thank you very much!
Mike Becker, Senior Instructor
Had many issues with this problems,some cars are flood cars that were fixed by replacing modules and fuse boxes,which fixed the issue,but many yrs later we end up trying to figure out this issues,not knowing it was a flood car four yrs ago ,creating many pins to corrosion.
Thanks alot for the video Mike. So i am right i thinking when you first hooked up to the PCM and TCM lines you used piercers on all 4 wires and then just to install the jumper you back probed yes?
Thanks
Dave
Hey David, my intial scope capture that showed the "bad" blue trace was back probed at the connector. I then removed that back probe and put my jumper wire in. The second back probing is what "fixed" my issue.
Mike Becker, Senior Instructor
Ok Mike thanks for clearing that up. I just saw the 2 piercing tools on your screenshot and thought you might have originally pierced all 4 and then just back probed the jumper. Just wanted to get it clear in my head, thanks again
Of course David, glad I was able to clear it up!
Mike Becker, Senior Instructor
Yes
Thank you for the indepth quick video.
Now to fix my $700+ dealership diagnose with already computer flash for the ecm. I didn't think to ask will that fix the problem for my u1000. But now u1000&u1001 are friends. How in the future to fix it....
Good video and good tips to diagnostic thank you
Hey Antonio, thanks for watching!
Mike Becker, Senior Instructor
Haha, love it. It was probably someone jabbing it with a back probe in the first place that did it.
Hey Mechanic Mindset, thanks for watching! Yeh, could be...who know's!
Mike Becker, Senior Instructor
Thank you for sharing your knowledge.
Thanks for watching David!
~Mike
U said u were working on a wisconsin vehicle. Are u located in wisconsin. I am looking for some one that can trouble shoot the electrical. If not can u recommend some one. I prefer not to be the guy that just starts replacing things. I already have 1500 into it. Mechanic said we just have to start replacing parts. Had 2 different places lookk at it. Any help would be appreciated.
Hello Beth Grabow, yes we are located in Fond du lac, Wisconsin. If you'd like, we can continue this conversation via email so it stays private. You can reach me at michael.becker@gotech.com
Thanks,
MIke
Had a Cadillac cts abs com issue. Eventually found the blue slide in wire retainer in the connector was broken and allowing the wire to back out when installed. No room to properly check connector. Only found the problem when i disassembled the connector in desperation!
hello mike what's the version of launch , autel and snap on are you using ??
These is a great check to the connector that could save $ 200 or more foa tcm reprogram or replacement.
Exactly! Thanks for watching!
Mike Becker, Senior Instructor
Good teaching, and thanks for the video👍👍👍👍👍👍👍👍👍👍
Thanks Salvador!!! :)
Mike Becker, Senior Instructor
Very interesting on your work
Omg thanks so much I can start my diag with the connector… Michigan cars bro 😭
Hey Chris,
Glad we could help! Good luck with your diagnosis
Ryan Wilsing, Technical Instructor
Good day i am talking to from trinidad and tobago my problem is that my mazda 3 keep going into forth gear while driving for it to go back to drive i have to take it off the engine and put it back on again for it to drive nomal again
I fixed a similar Mazda my buddy a mechanic replaced with new tcm, and still didn't work checked for tcm power signal with my autell no power did connector wiggle test power came on removed plug retighned terminal was fixed
Awesome Alejandro! Glad you were able to get it all fixed up :)
Mike Becker, Senior Instructor
Sir Good diagnose
I have question if any of them control module defective how to diagnose
With this whole pandemic going on right now, there has been a lot of cases of male to female pin problems 😁 usually ends up in a no communication 😆
Hey Hektor, I have no idea what it is that you're talking about ;) haha!
Mike Becker, Senior Instructor
Great video Mike! One question..How did probe to capture the bad waveform? You mentioned at the tcm connector, but I’m kinda confused. Wouldn’t back probing show a good waveform even if there is no contact between male and female pins?
Hey OC Diagnostics, my initial back-probing that captured the bad waveform was a bad connection on the back side of female pin. So, if I had a good connection then yes, it would have shown a good waveform.
Mike Becker, Senior Instructor
Great job ❤❤
You can fix very fast, Thank for this class.
Hey Manuel, not very fast on this one...haha!
Mike Becker, Senior Instructor
Very educational!! Thank you!! 😊
Thanks for watching !
Where can I get a tcm that's programmed for my vin?
At least you double-checked your work before returning it to the customer. As the saying goes, "Measure twice, cut once." That's still better than tossing a TCM at it for nothing like the customer did in the first place.
Hey Joseph, thanks for watching! It's funny, when working on cars I always apply that...woodworking...ugh let's just say I have a lot of waste, haha!
Mike Becker, Senior Instructor
it's possible the tcm was bad and they/other shop damaged the connector pin testing it with force and t-pins
I got it: how do you know that female connector is bad if you don't get lucky, the story of men's life, and also it was a good video!
Hey Joe, thanks for watching!
Mike Becker, Senior Instructor
I have u1001 code on 2014 Chevy impala trying to figure out if I gotta replace my wires or my whole tcm assembly
So if you could do it again what would you do differently?
Hey J. Angus, I would have pierced the wires and seen that I had communication reaching the TCM connector. I would have then checked power and ground to the TCM. Comm, power and ground would have lead me to thinking it was a TCM issue, but I always verify pin tension prior to ordering a module...so I would have found it then. No need to tear the harness apart like I did.
Mike Becker, Senior Instructor
@@GoTechTraining Pierce first, ask questions later brother. Thanks for the solid content.
Hi Mike. Thank you for another great vid. Unrelated question; Around here, we have NAPA, Aotozone, Pep Boys and Advance Auto. All of their products are in their own packaging. Where can I get your products (preferably with your packaging)? I don't see them locally.
Hey P Sav, thanks! Many of our products come in those store branded packages. There are some places you can buy stuff in a Wells or WVE box, but its not as easy to come by as the big stores. If you're ever looking for a part and want it to be ours, give our techline a call. They can tell you where you can buy it.
Mike Becker, Senior Instructor
I owned a shop from 90 to 2000 I wish we had the info back then that ur audience has available to them now
I currently have this U0101 code on my 2014 Chevy Malibu. When the TCM is down, the car is stuck in third gear (limp mode) and gear shift is not illuminated. When I drive 20-30 minutes in limp mode , the TCM does come back and stays as long as I keep driving. When I shut the engine off and wait about 10 minutes and turn engine back on, the TCM fails again, so it's an intermittent issue. Chevy dealership has no answers after I paid them 224 dollars in diagnostic fees. They wanted an additional $1300 to further diagnose it and obviously I declined that, so now I'm stuck with a TCM that goes in and out. Very frustrating. I have taken that TCM connector off and on so many times that I've lost count. Nothing is working.
Thank you you sir. Have a Merry Christmas and a happy new year!
Hey Luis, thanks for watching and Merry Christmas and Happy New Year to you as well!
Mike Becker, Senior Instructor
Same thing happened when I was running parameter diagnostics on my TCM and T/C my Jeep was making a lot of loud noises from relays. Got better after a few restarts
Interesting,, will have to keep this in mind,,
Omg where are you located at. I wish you could do this to my 2015 GMC Terrain
Hey, we're located in Fond du lac, Wisconsin. Whats going on with the Terrain!?
Mike Becker, Senior Instructor
I swear these dealers and mechanics in Michigan are just dumb or lazy. Been to the dealership 3 times and they can’t figure it out.
@gotech. My transmission is stuck in limp mode and responds slowly in reverse to 80% pedal pressure. only DTC U0101; U0402. It's TORQUE FLITE 8HP70 transmission. I can't believe my transmission has failed at 40934 mi.
Good information
How do i know for sure if the TCM is bad and needs to be replaced? or there is no way to tell ?
What software are you using to view and isolate the various circuits? And are you using a Snap-on D-9 Scanner?
Where do you buy your wiring diagrams?
Check out AllData. They have a DIY version that you could look into.
Mike Becker, Senior Instructor
I really need that scanning tool for Mazda please, from Zambia
Thank you for sharing your diagnostic process, sometimes the simplest thing is in front of us. Keep it simple ;-)
Hey Sudako, thanks for watching. Have you heard of the K.I.S.S method? Keep it simple stupid :)
Mike Becker, Senior Instructor
So was it the TCM connector?
Excelente información gracias.
I wld love to c u implement today to yesteryear testing
Good job
Hey mike how r u brother? Keep up the good work 👍
Hey Pat, doing well, thanks. And you? Thanks for watching!
Mike Becker, Senior Instructor
@@GoTechTraining everything good brother.whats new at gotech?
EXCELLENT JOB CLEAR INFO!
did you have to go to a dealer ship to get it
was it a power line or ground?
Does the TCM need to be reprogrammed if replaced? Purchased a used one and replaced mine but didn't know they had to be programmed
WOW, I will try that. Thank you.
I can’t even locate TCM on the car I’m working on (2011 Altima Hybrid) . Identifix illustration is different. Very frustrating. Most thing I hate about electrical is figuring out which wire is which.
Do you have a website to show exactly pictures what you did because I have sent my tcm back to many times (all Computer repair parts). I just got it back and it's still acking up
Great video
Great video!
Thanks Santer Auto Repair LLC!!!
Mike Becker, Senior Instructor
I have a similar issue with my mazda 3 2005 2.3. It jumps when goes into second gear when engine still cold mostly . Could this be the TCM as well or wiring or conector ?
Thanks brother thats good work i probably would had miss it
Hey Antwon, I don't think you would have missed it :)
Mike Becker, Senior Instructor
Hey man I have a 2007 Mazda 3 and the TCS light comes on as well as the check engine and when I put the car into drive it goes into 3rd gear and when I pass reverse it gives the car a really rough shape and same when I put it into reverse. I’ve replaced the map censor within the car in hopes it would bring the car out of limp mode. Turned the car on after I replaced the map censor and it went into first gear and reverse fine without the rough shake to the car. Went back the next day and it’s doing the same thing. Not sure if it’s because of my connection to the TCM that would be my next guess from watching your video. Any suggestions before I check the TCM?
Thank you for this great lesson. Apreciated
Hey Ruben, thanks for watching!
Mike Becker, Senior Instructor