There's always a certain level of satisfaction when you can hypothesize the possibilities of which component is the issue with some basic symptoms and known repair attempts and be right. It would be nice if every diy'er could afford a good diagnostic scanner and oscilloscope. Knowing the module was replaced and the problem still exists, my instincts told me abs sensor or wire issue due to the brake work that was done. It isn't uncommon for a wire to accidentally get pinched or yanked because it wasn't disconnected and moved out of the way (I learned that many years ago on my own vehicle). Not having the good diagnostic tools, I'd have gone right to checking resistance on each and check wiring and physical inspection of the actual sensors and reluctor rings. Yes, ground level electrical diag is great but the average person doesn't have the expensive tools to do that. If they don't have the scratch to buy those, they don't have the money to pay a shop (at least not a reputable shop.) Great work, as always, Ivan! I've learned a ton from you over the years and just had to modify my own line of attack due to not having the truly proper diag tools. Most of the time, I get it right with my modified methods. But still, I still occasionally get it wrong. Thankfully the parts cannon hasn't been fired much 😊.
Nothing wrong with your procedure IVAN, thank you for the long version. circa 2002 I went to a BOOTCAMP with John Anello in Northern New Jersey for a week on the road with him (AUTO TECH ON WHEELS, not sure if you have heard of him?) to hundreds of shops to diagnose hundreds of vehicles. One had an unwanted ABS activation at slow speed, he hooked up the 4 channel scope to a connector under the carpet, went for a drive and one sensor was a smaller signal that the others, problem found, told the shop to replace the WSS on that corner and we were done with a test drive and experience. Thank you for all your tutorial videos and different ways of finding and proving a problem, cheers.
We used to have ABS codes for the front sensors, and we would find the axle bearing assembly was worn out giving side to side movement when the tire/wheel assembly was moved. As the bearing assembly was being replaced the sensor was also replaced because of groves cut into the sensor's bottom. All this work done because the ABS came on at 5 MPH or less. The sensor was a great safety because the bearing assembly was breaking up internally. Good one Ivan!
My thought was the tone ring had moved but he didn’t show the after pics because someone else did the job. If the tone ring or the bearing is bad it won’t take long for that next trip to Florida to take a detour.
That brings a whole new meaning to " I will wait at the shop " while it's being worked on. I am guessing someone in the family was thinking new horse barn!
That's why I keep preaching the power of a good scope. I am surprised the shop that replaced the module didn't also replace the sensors. I guess the parts canon was low on ammo.
@@PineHollowAutoDiagnostics Even with no voltage you could figure it isn't generating the voltage from dynamo effect. Would be curious if new sensors now give 10 volts.
@@PineHollowAutoDiagnostics except the parts cannon isn't propelled by common sense. The trigger man was already psyched out by magic pixies, and service data had him completely wrong footed. At that point it just had to be the magic pixie generating module.
As always from Ivan, a nice thorough troubleshoot and diagnosis. The scope is definitely a must have. Unfortunately most auto shops don't have them. Ehich is why they resort to the parts cannon. In this case they fired the wrong cannon with the ABS module instead of the sensors.
It's just ridiculous the amount of gear necessary to diagnose vehicles . I lost count of how many test leads were hanging under that vehicle. Scopes, laptops, and scan tools galore. My next buy will be something really simple from 1950.😊 Good job as usual.
Nice diagnosis on those big RV, i did one few years ago. I overhauled all the brakes and i did replace the abs sensors as they were just like that on the video!! Owner were happy about all the repairs i did. Got paid and it's outta here lol. Nice video!!
I had a very similar issue on a Lexus RX330 where the gap was the cause of an abs issue. These sensors can be very sensitive to gap distances. Great study Ivan.
Nice video, Ivan! The minute you mentioned (in the beginning of your video) that the ABS would kick in when coming to a stop, I was 90% sure that a sensor, was going to be the problem. The same thing happened to my 2000 Ford Ranger. One day, as I was approaching a stop sign, the check engine light came on, and when I was about to stop, the ABS kicked in for no reason, as it was a warm, summer day. The funny thing was, it would only activate while coming to a stop, "under" 10mph - and it made me roll through a couple of stop signs farther than I wanted it to! Did a little research, did some testing and here it was the front right sensor that was bad. Replaced both fronts, and all was good again. BTW, Ivan, "the most annoying Ford" (Mountaineer) is still running great! Thanks again for all the help with that issue!!!
Rust belt claims another victim. I felt actual physical relief for you at the end when "Owner had his local shop replace the sensors" popped up. The thought of dealing with those wheels hurt my back!
Another great diagnostic video. Full credit to the shop that had the brains to unplug the sensors. That left the brakes as effective as they possibly could be. Thank you for your content, its great. For techs on a budget, don't overlook basic scopes. You do get what you pay for, but there are lots of good budget options. PICO have a 2 channel, non automotive scope for around the cost of a tank of gas. Its NOT as good as their 4 channel automotive specialist scope. But it would have done this job, and many others, and there are plenty of other vendors with sharp products at modest prices. If you need a hammer, buy a hammer. If you are using it 24/7 buy the best hammer you can get. If you use it twice a year, a $40 hammer may well be the solution you need. Its still better than using the side of the pliers.
good video , older vehicles are like that , replacing parts can disturb other things and i try to be mindful when working on older vehicles not to try create more problems
Had a similar issue with a Ram a while back, left front also. Common rust jacked scenario. Took some time to dig the old one out, prefer not to drill, but it fixed the problem. Looks like someone “ painted “ the frame on that unit. That’s the worst thing to do, unless You like to speed up the rusting process.
Wow! That's a MonsterHome 🙂 Great diagnostic, Ivan! Impossible without a scope! It had to be tonewheel / sensor related, but this was a devious little one 🙂 Glad new sensors cured it.
Ivan that was a great trace on the 2 sensor signals. The air gap is obviously out of spec. For what it's worth when I was still working and a vehicle had an unwanted abs activation while almost stopped it was usually a bad wheel bearing. Good luck on getting the sensors out.😂
My first speed sensor was a carlton fisk baseball card attached to the front forks banging off my bicycle wheel spokes. The faster or slower i went, i could hear a higher or lower frequency tone😅😊
Balloons sounded more like hot rod exhaust, and isn't that really why we did it. No helmets either and yeah we crashed occasionally like when going off jumps.
You truly are amazing and from the variety of vehicles that come your way you have quite a following Ivan. "Welcome to Pine Hollow Auto Diagnostics...today we have a strange car that kinda looks like a 747 that was towed to us from Texas with a bad ABS Issue and the pilot/Owner is looking to avoid the parts cannon".......LOL You Rock Ivan!!!!
Looks to me like the sensor is not much more than a hall effect transistor and a magnetic field. Each tooth of the tone ring merely deflects the magnetic field and so the hall effect transistor changes state. Because the sensor has a magnetic field, it will attract any ferrous material and build up a coating. The coating will not only inhibit the magnetic field deflection from each tone ring tooth as it passes by, it will also be a sponge for moisture and debris, and thus increasing corrosion on the sensor. Keeping both the sensor and the tone ring areas clear of rust AND also keeping the gap to spec are essential to proper operation.
I really like Ford's diag flowcharts! ...When they're correct. It can be a quick and dirty way to understand system operation and get all your key test locations in one go. I've run into documentation issues like this on these Ford blank chassis vehicles before, and it is such a royal pain in the butt! An F59 caused me a week of trial and error testing, and was responsible for me raising my rates for commercial and upfitted vehicles. :(
One look at the sensor all crusty and flakey would have them replaced before the module. That is just me. My DIY sense of doing the easy part first. I would not have looked at the module because it was activating. The scope is the way to go, but most Diyers are not so fortunate. Nice diag Ivan.
Nice. I am convinced that those are inductive sensors. No circuit inside. Just an inductor, a permanent magnet an an iron core. Sensors that produce voltage. The voltage depends from the speed of the gear (how fast the magnetic field changes) and the gap (strength of the magnetic coupling). That type of sensor will "read" as defective in low speeds when the gap is large.
I would have loved to see you drive that motorhome, Ivan. I am certain you could drive anything with a steering wheel; couldn't be much different than a 1971 Zaporozhets 966, right? The first car I ever owned with anti-lock brakes was a 1987 Lincoln Mark VII. On that car you had to adjust the distance the ABS sensor was from the tone wheel. I remember using a feeler gauge to do that. While you state an oscilloscope is essential to diagnose this problem remember YOU know how to use one of these instruments. GREAT VIDEO!
Had the exact same issue in my audi. Couldnt figure it out, also thought the ABS Module is dead. But then I got the sensors out, one was clean, one was full of rust because the driveshaft on that side was never done and the ring started corroding. Cleaned everything, put it back together and brakes were normal again. Sometimes its that simple
Chevys are famous for ABS coming on under 5mph. Will usually pull one direction or the other when ABS comes on. Almost all ways bad front wheel brng. Direction of pull is opposite to the bad side.
working on big rigs it was common when doing brake jobs the sensors would get knocked in(mounted with a loose press fit). so ya got used to pulling and cleaning them and reinstalling after puting the brake drum/wheel hub on. never failed some rookie wanting to make flat rate slamming a brake job had a come back. yep sensor gap was too wide.
Had a similar problem on my 2004 GMC Envoy. Measured wheel sensor with a DVM and had half as much amplitude on one sensor (sorry don't remember levels). In removing the sensor with lower levels, found rust and corrosion under mounting flange. Cleaned area and got better levels.
Fords do that when you dont seat a speed sensor correctly in its little hole.. itll read right on the tone ring but will give you that 5mph abs activation.. ive had to simply remove the sensor and push it back in and jiggle it in there just perfect before bolting it back down..
Mazda 3 had same issue. It kept throwing a transmission speed code. Owner had brakes and wheel bearing replaced right before the problem started. While setting up to measure ABS sensor, I noticed it looked installed at an odd angle. Cleaned up the surfaces, reinstalled the same sensor. Problem solved for 20,000 miles so far.
More than likely that sensor damage can be traced back to the shop that did the front brakes, especially if they turned the rotors (which it appears they did). They are magnetic, and can hold on to a lot of shavings which get ground down by the reluctor rings. Usually the sensor is the part to fail in these systems especially if a wheel bearing is loose or failing, and a shop isn't careful working around the sensors.
I said it before! "There is NO SUBSTITUTE for Brains!" The orignial shop shold have replace the sensors. The vehicle deserves to have proper brake activation. When they should have used the Parts cannon, (2 sensors, both old, shot) they did nothing??? Great video....
I wonder if the an impact hammer (or other larger impact producer) was used during the brake job? Could have been the first time the brake system was touched. Did the RV even have 75K on it? My guess is the rotor and/or wheel were on "good and tight", and give a good fight on the way off. The result on the driver side was the ABS sensor re-gapping.
DYER's on these old sensors, they can be checked with a DVOM set to AC. Good reading spinning the wheel 400mv. or higher good. Get down to 250mv you start to get ABS activation when coming to a stop.
We have a similar sort of dog to the one you have on your phone on the video,we adopted her about 14 months ago because her owner died & his partner couldn't afford to look after more than 1 dog. According to her papers she's a Jack Russell Terrier Chihuahua crossbreed but I think that she's more of an Australian Terrier like the third dog my parents owned beginning 40 years ago. It has taken a while for her to settle down because she used to bail me up all the time & she will bark at anyone whose walking out of the back door in the house still. It took her 1 year to get used to be where she would sit on my lap while I am watching television or if I am lying on the bed she will jump up onto the bed & lie on it with me. A couple of my aunties used to have silky terriers in her time,we prefer to own a terrier because they're a much more manageable dog which is good for children as well. My dad had to give away a blue cattle dog 40 years ago because he jumped up & bit me on the arm so my auntie who was one of them whose friends were moving away had to give their Australian cross Terrier away to us when they moved !
Rust jacking ( to far away from tone ring) and metal debris on abs sensor magnets cause bizarre issues . Excellent 👍 Not many people want to work on these big RVs Generator, Inverter,HVAC , Water sewage Washer dryer etc etc Would be a good business for you Ivan so much variant technology on these and most people who own such have the money to pay for proper diagnosis repairs . I grew up as marine mechanic similar tech .
Rust will always be a problem in the northeast. That is a huge air gap for sure. GM has some issues too with their speed sensors getting crud buildup on them effecting the signal. Heck, probably all manufacturers do in some shape or form.
When a new problem shows up after maintenance, it's dang near assured that the new problem was induced by something that got previously touched. I've seen it many times. The "parts cannon" ABS module replacement was unfortunate.
Really important also is change out the brake fluid on these F- series rigs ! Forbid losing your brakes driving down a mountain ! Ive seen even 16,000 lb trucks do this a few times !
Bounder by Fleetwood. When I was working on those PITA overloaded hunks of fun, I called it Flounder by Beetwood. Yuck! So many of those over the years. Oversized beasts driven by old people. ABS seems sorta silly. Good luck locking up a wheel on that thing. Quite dangerous vehicles, IMO.
Very nice work as per usual, I see the owners enjoying your beautiful landscape like I would also. Do you use pico library to compare apples to apples? Thank you for another learning experience
The problem is clear, and obvious, a lot of rust on the sensor, and need to be changed even without any problem yet, don't take chances, but the other shop went after the ABS module, if I am the one who did the brake job I will.recommand strongly charging that rusty ABS sensors, that is part of the brake system that can cause serious crashes if the signal is bad and cause the ABS to activate inaproberelly.
Common GM pickup ABS issues caused by rust buildup and raising the sensor off of the hub causing excessive tone ring gap. This causes the ABS to active when truck speeds were under 7MPH.
Budget diag tips for you who don't have an oscilloscope: Listen to the signals using a (small battery powered) guitar amp, or any other type of amp with a high impedance input (like the gramophone input on a 50+ year old transistor radio). Too wide gap would be noticeable as a difference in volume. Bad tone rings will be noticeable as beat frequency modulating the tone signal (like a wah-wah pedal, kind of sort of). (Of course even the cheapest budget oscilloscopes for $20-$100 are better, but if a amp is what you happen to have you can get away using that instead)
Had a relative was thinking about putting a window on the storage door where the cats litter box is. the cat can go down from inside the rv. Thought that should get some strange looks from other cars. LOL
Looking at the video I could not see jack stands while you were working. As an old motor home owner that is a no no. I have worked under my MH with just the hydraulic jacks but after countless warnings I began using jack stands.
Ivan, you tried to analyse the problem from a voltage and resistance point of view. Some circuits work from a current point of view. I suggest you read up on the operation of a 20mA current loop. In the end your electrical tests proved nothing; it was the visual inspection which diagnosed the problem.
The owner is fortunate that you would work on his RV. I never liked it because of the lack of good service info, hard to find the correct parts and having the owners camping out in the service bay. I realized that it is their home on the road, but that is why there are rental cars and motels. I had to perform a transmission repair on a class C while the owners, with the blessings of the SM, sat in the next bay in folding chairs. Nice people, but come on! That was my last week at that shop.
My truck used to do this randomly. I did a full brake job and there was so much junk in the tone ring teeth it was basically round. Cleaned it and never happened again.
Lehto just clicked next vid.... I was shocked how much trouble it is getting parts and info. I had to drive 125 miles to a bone yard just to get a transmission dipstick for a bus conversion. It is still a ford drive train, why do they care what is bolted to it. Needed the motor for the door as well, nada anywhere, then saw the city ran the mini busses so called them. "we don't sell parts." I know, but you have to buy parts from somewhere. Got their supplier and got the motor. turns out it was changed from a simple reverse polarity to a 3 wire signal. So, added an extra DPDT relay to reverse the motor rather than run a signal wire through the chassis to the motor.
Old school techs: oscilloscopes aren't that complicated... You put the signal on a screen. Two elements to adjust: (-1-) how fast the trace/sweep travels left to right, and (-2-) what amplitude the signal appears as. The screen has LITTLE SQUARES and the scope front panel has controls for milliseconds or microseconds (etc.) per square for sweep horizontally and volts or millivolts (etc.) per square deflection vertically. You can find scopes for LOTS of money and some for CHEAP. There's all sorts of classes in RUclips on how to use a scope. A VOM measures AC but can't tell you if it's sinewave, squarewave, trianglewave, etc. A VOM measures DC but won't see noise. YOU GOTTA HAVE A SCOPE. BTW. .. some scopes AUTOMATICALLY adjust sweep and amplitude with resulting values DISPLAYED on the screen.
I was trained on one of the big Sun analyzer machines in the early 90s. Had the big swing arm with every cable and attachment imaginable, back in those days. We had a guy working on a motorhome that was pinging. Dude did heads, timing chain, distributor and wanted to keep throwing things at it until the owner got frustrated and hooked it to the Sun analyzer. It had a bad alternator. That was the only time in the years I worked for him that I saw him completely lose his s*@t. I learned from observation the value of a scope. ;)
@@farmermiyagi1338 i used the old sun monster ours had a gas analyzer in that same cabinet, it was a beast to move around a 2 bay garage , now i have a scan tool that fits in my front seat with my DVM and a good scope is in my future. I only do this part time now. But i still remember the Sun instructor showing us all of the options and the boss had us putting it on every car that came in for a tuneup then!
@@KStewart-th4sk All I know (this was over 30 years ago) was that there was a serious problem with the output signal from the alternator. The wave pattern on the scope was crazy. I would assume that it simply did not have enough power to drive the ignition system properly. Either way, a new alternator got rid of the ignition ping. Ivan might be able to explain it better than I can. I'm just a tech, he's the genius. ;)
@@johnchambers12 Oh yes, it had a gas analyzer. In the late 90s I came back here to central Arkansas, and got laughed at a lot for missing my gas analyzer. Now we have built in sensors for that though. If you can trust them to function properly that is.
It's soo funny how often basic mechanical systems are ignored and they go straight to the computer. Me mudder was sitting her watching this vid and giggling. Shes an ex truck and coach mechanic. She said problem arose after brake work, check work and abs sensor gap as they can get knocked around, sometimes they can be fixed but often replaced . Imagine a 75 year old woman calling it at start of vid
There's always a certain level of satisfaction when you can hypothesize the possibilities of which component is the issue with some basic symptoms and known repair attempts and be right. It would be nice if every diy'er could afford a good diagnostic scanner and oscilloscope.
Knowing the module was replaced and the problem still exists, my instincts told me abs sensor or wire issue due to the brake work that was done. It isn't uncommon for a wire to accidentally get pinched or yanked because it wasn't disconnected and moved out of the way (I learned that many years ago on my own vehicle). Not having the good diagnostic tools, I'd have gone right to checking resistance on each and check wiring and physical inspection of the actual sensors and reluctor rings. Yes, ground level electrical diag is great but the average person doesn't have the expensive tools to do that. If they don't have the scratch to buy those, they don't have the money to pay a shop (at least not a reputable shop.)
Great work, as always, Ivan! I've learned a ton from you over the years and just had to modify my own line of attack due to not having the truly proper diag tools. Most of the time, I get it right with my modified methods. But still, I still occasionally get it wrong. Thankfully the parts cannon hasn't been fired much 😊.
A DIYer can afford a good scanner and scope today for less than $200 for both, cheers.
Nothing wrong with your procedure IVAN, thank you for the long version. circa 2002 I went to a BOOTCAMP with John Anello in Northern New Jersey for a week on the road with him (AUTO TECH ON WHEELS, not sure if you have heard of him?) to hundreds of shops to diagnose hundreds of vehicles. One had an unwanted ABS activation at slow speed, he hooked up the 4 channel scope to a connector under the carpet, went for a drive and one sensor was a smaller signal that the others, problem found, told the shop to replace the WSS on that corner and we were done with a test drive and experience. Thank you for all your tutorial videos and different ways of finding and proving a problem, cheers.
We used to have ABS codes for the front sensors, and we would find the axle bearing assembly was worn out giving side to side movement when the tire/wheel assembly was moved. As the bearing assembly was being replaced the sensor was also replaced because of groves cut into the sensor's bottom. All this work done because the ABS came on at 5 MPH or less. The sensor was a great safety because the bearing assembly was breaking up internally.
Good one Ivan!
My thought was the tone ring had moved but he didn’t show the after pics because someone else did the job. If the tone ring or the bearing is bad it won’t take long for that next trip to Florida to take a detour.
Kudos to the owner for keeping this rig going, looks great. Today's production is full of quality/dependability issues.
Ivan, do you trust those hydraulic jacks?
Excellent detective work Ivan. You do an incredible job showing exactly what is going on, culminating in the fantastic pictures of the gaps. 👍👍👍
That brings a whole new meaning to " I will wait at the shop " while it's being worked on. I am guessing someone in the family was thinking new horse barn!
As always Ivan got it fixed with no unnecessary parts and added expense.
Thorough diagnose! Wish that was common by shops.
most customers won't pay for diagnostic. So they get what they pay for.
That's why I keep preaching the power of a good scope. I am surprised the shop that replaced the module didn't also replace the sensors. I guess the parts canon was low on ammo.
Used cannon. Even Ivan couldn't get sensors. 🤔
You would think that sensors would be loaded first in the parts cannon...before the module 🤔
@@PineHollowAutoDiagnostics Even with no voltage you could figure it isn't generating the voltage from dynamo effect.
Would be curious if new sensors now give 10 volts.
@@PineHollowAutoDiagnosticsBut they aimed the parts cannon at the owners wallet, that's why
@@PineHollowAutoDiagnostics except the parts cannon isn't propelled by common sense. The trigger man was already psyched out by magic pixies, and service data had him completely wrong footed. At that point it just had to be the magic pixie generating module.
Awesome diagnosis as always. Great job, Ivan.
As always from Ivan, a nice thorough troubleshoot and diagnosis. The scope is definitely a must have. Unfortunately most auto shops don't have them. Ehich is why they resort to the parts cannon. In this case they fired the wrong cannon with the ABS module instead of the sensors.
Don't worry about the glare. You have enough to do with the analysis and filming for us.
Thanks
It's just ridiculous the amount of gear necessary to diagnose vehicles . I lost count of how many test leads were hanging under that vehicle. Scopes, laptops, and scan tools galore. My next buy will be something really simple from 1950.😊 Good job as usual.
Nice diagnosis on those big RV, i did one few years ago. I overhauled all the brakes and i did replace the abs sensors as they were just like that on the video!! Owner were happy about all the repairs i did. Got paid and it's outta here lol. Nice video!!
I love hearing your gears turning when you diagnose an issue. 🤣Most entertaining & informative. Great stuff, Ivan. 👍
I had a very similar issue on a Lexus RX330 where the gap was the cause of an abs issue. These sensors can be very sensitive to gap distances. Great study Ivan.
Nice video, Ivan! The minute you mentioned (in the beginning of your video) that the ABS would kick in when coming to a stop, I was 90% sure that a sensor, was going to be the problem. The same thing happened to my 2000 Ford Ranger. One day, as I was approaching a stop sign, the check engine light came on, and when I was about to stop, the ABS kicked in for no reason, as it was a warm, summer day. The funny thing was, it would only activate while coming to a stop, "under" 10mph - and it made me roll through a couple of stop signs farther than I wanted it to! Did a little research, did some testing and here it was the front right sensor that was bad. Replaced both fronts, and all was good again. BTW, Ivan, "the most annoying Ford" (Mountaineer) is still running great! Thanks again for all the help with that issue!!!
Oh man that dinger was so very annoying 😂
Awesome diagnosis and conclusion! Rust is a money maker for sure! Thanks!
Rust belt claims another victim. I felt actual physical relief for you at the end when "Owner had his local shop replace the sensors" popped up. The thought of dealing with those wheels hurt my back!
Good morning Ivan! That's a HUGE rig!
That's what she said
Another great diagnostic video. Full credit to the shop that had the brains to unplug the sensors. That left the brakes as effective as they possibly could be. Thank you for your content, its great. For techs on a budget, don't overlook basic scopes. You do get what you pay for, but there are lots of good budget options. PICO have a 2 channel, non automotive scope for around the cost of a tank of gas. Its NOT as good as their 4 channel automotive specialist scope. But it would have done this job, and many others, and there are plenty of other vendors with sharp products at modest prices. If you need a hammer, buy a hammer. If you are using it 24/7 buy the best hammer you can get. If you use it twice a year, a $40 hammer may well be the solution you need. Its still better than using the side of the pliers.
good video , older vehicles are like that , replacing parts can disturb other things and i try to be mindful when working on older vehicles not to try create more problems
Nice diagnosis Ivan.
Had a similar issue with a Ram a while back, left front also. Common rust jacked scenario. Took some time to dig the old one out, prefer not to drill, but it fixed the problem. Looks like someone “ painted “ the frame on that unit. That’s the worst thing to do, unless You like to speed up the rusting process.
Wow! That's a MonsterHome 🙂 Great diagnostic, Ivan! Impossible without a scope! It had to be tonewheel / sensor related, but this was a devious little one 🙂 Glad new sensors cured it.
Great detective work thanks for sharing
Ivan that was a great trace on the 2 sensor signals. The air gap is obviously out of spec. For what it's worth when I was still working and a vehicle had an unwanted abs activation while almost stopped it was usually a bad wheel bearing. Good luck on getting the sensors out.😂
My first speed sensor was a carlton fisk baseball card attached to the front forks banging off my bicycle wheel spokes. The faster or slower i went, i could hear a higher or lower frequency tone😅😊
Balloons sounded more like hot rod exhaust, and isn't that really why we did it. No helmets either and yeah we crashed occasionally like when going off jumps.
You truly are amazing and from the variety of vehicles that come your way you have quite a following Ivan. "Welcome to Pine Hollow Auto Diagnostics...today we have a strange car that kinda looks like a 747 that was towed to us from Texas with a bad ABS Issue and the pilot/Owner is looking to avoid the parts cannon".......LOL You Rock Ivan!!!!
Looks to me like the sensor is not much more than a hall effect transistor and a magnetic field. Each tooth of the tone ring merely deflects the magnetic field and so the hall effect transistor changes state. Because the sensor has a magnetic field, it will attract any ferrous material and build up a coating. The coating will not only inhibit the magnetic field deflection from each tone ring tooth as it passes by, it will also be a sponge for moisture and debris, and thus increasing corrosion on the sensor. Keeping both the sensor and the tone ring areas clear of rust AND also keeping the gap to spec are essential to proper operation.
Another great diagnosis, Ivan! Thanks!
The holy grail is the vehicle is self-jacking. SWEET.
This video popped up as I was driving my F450 chassis Jayco Class C. Brakes work just fine...
the minute you said brake job I pictured Eric O and the "Dawg" rattling trash right into the air gap
Persistence pays! Great job.
Another wonderfully done job!
Gotta love built in jacks. Indy cars and motorhomes. 😉
Nice long straight driveway you got there. Prefect for small aircraft to fly in for a quick diagnose.
That'll get Ivan some practice with the borescope. Those flyboys love peeking in on the cylinders and valves.
I really like Ford's diag flowcharts! ...When they're correct. It can be a quick and dirty way to understand system operation and get all your key test locations in one go.
I've run into documentation issues like this on these Ford blank chassis vehicles before, and it is such a royal pain in the butt! An F59 caused me a week of trial and error testing, and was responsible for me raising my rates for commercial and upfitted vehicles. :(
Great job of analysis.
One look at the sensor all crusty and flakey would have them replaced before the module. That is just me. My DIY sense of doing the easy part first. I would not have looked at the module because it was activating. The scope is the way to go, but most Diyers are not so fortunate. Nice diag Ivan.
Can't wait to c the results.
Great job Ivan! At least the tone rings were in good shape. Replacing what was needed to fix them would have been more expensive.
Nice. I am convinced that those are inductive sensors. No circuit inside. Just an inductor, a permanent magnet an an iron core. Sensors that produce voltage. The voltage depends from the speed of the gear (how fast the magnetic field changes) and the gap (strength of the magnetic coupling). That type of sensor will "read" as defective in low speeds when the gap is large.
I would have loved to see you drive that motorhome, Ivan. I am certain you could drive anything with a steering wheel; couldn't be much different than a 1971 Zaporozhets 966, right? The first car I ever owned with anti-lock brakes was a 1987 Lincoln Mark VII. On that car you had to adjust the distance the ABS sensor was from the tone wheel. I remember using a feeler gauge to do that. While you state an oscilloscope is essential to diagnose this problem remember YOU know how to use one of these instruments. GREAT VIDEO!
Had the exact same issue in my audi. Couldnt figure it out, also thought the ABS Module is dead. But then I got the sensors out, one was clean, one was full of rust because the driveshaft on that side was never done and the ring started corroding. Cleaned everything, put it back together and brakes were normal again. Sometimes its that simple
Chevys are famous for ABS coming on under 5mph. Will usually pull one direction or the other when ABS comes on. Almost all ways bad front wheel brng. Direction of pull is opposite to the bad side.
Great job but did you recommend using the original ABS module?
Good job ivan
working on big rigs it was common when doing brake jobs the sensors would get knocked in(mounted with a loose press fit). so ya got used to pulling and cleaning them and reinstalling after puting the brake drum/wheel hub on. never failed some rookie wanting to make flat rate slamming a brake job had a come back. yep sensor gap was too wide.
Thanks Ivan!
Had a similar problem on my 2004 GMC Envoy. Measured wheel sensor with a DVM and had half as much amplitude on one sensor (sorry don't remember levels). In removing the sensor with lower levels, found rust and corrosion under mounting flange. Cleaned area and got better levels.
Fords do that when you dont seat a speed sensor correctly in its little hole.. itll read right on the tone ring but will give you that 5mph abs activation.. ive had to simply remove the sensor and push it back in and jiggle it in there just perfect before bolting it back down..
Had the same problem on an explorer. Removed front sensors, cleaned all the junk off the tip and the well they sit in, reinstalled... problem solved.
Mazda 3 had same issue. It kept throwing a transmission speed code. Owner had brakes and wheel bearing replaced right before the problem started. While setting up to measure ABS sensor, I noticed it looked installed at an odd angle. Cleaned up the surfaces, reinstalled the same sensor. Problem solved for 20,000 miles so far.
I’ve got an RV and it’s a needy beast…but do the maintenance and they will do good for you.
More than likely that sensor damage can be traced back to the shop that did the front brakes, especially if they turned the rotors (which it appears they did). They are magnetic, and can hold on to a lot of shavings which get ground down by the reluctor rings. Usually the sensor is the part to fail in these systems especially if a wheel bearing is loose or failing, and a shop isn't careful working around the sensors.
Great job brother, as always
I said it before! "There is NO SUBSTITUTE for Brains!" The orignial shop shold have replace the sensors. The vehicle deserves to have proper brake activation. When they should have used the Parts cannon, (2 sensors, both old, shot) they did nothing??? Great video....
That bug that came across the screen made me jump as I thought it was on the iPad that I was using!😂😂😂
Teslong hardware bug
@4:17 in the symptoms sure resemble the old GM front wheel bearing slop issue.
19:12 owner taking in the sun, thinking "I love automotive work, I could watch it all day".
I wonder if the an impact hammer (or other larger impact producer) was used during the brake job?
Could have been the first time the brake system was touched. Did the RV even have 75K on it?
My guess is the rotor and/or wheel were on "good and tight", and give a good fight on the way off. The result on the driver side was the ABS sensor re-gapping.
Great work!!
great video!
Thank you so much
I've been hear . Had the tone ring slip on the rotor but by hand cold it was tight .when hot I could take the tone ring off effortlessly
Special guest at 23:26 little homie made it to the big times. "Hi mom! I'm on TV"
well done.
Great Saturday morning video
Comes w/ it's own TRUCK JACK !! 🤣
DYER's on these old sensors, they can be checked with a DVOM set to AC. Good reading spinning the wheel 400mv. or higher good. Get down to 250mv you start to get ABS activation when coming to a stop.
nice one ivan I fix anything but then Im a litle better set up for big stuff
We have a similar sort of dog to the one you have on your phone on the video,we adopted her about 14 months ago because her owner died & his partner couldn't afford to look after more than 1 dog.
According to her papers she's a Jack Russell Terrier Chihuahua crossbreed but I think that she's more of an Australian Terrier like the third dog my parents owned beginning 40 years ago.
It has taken a while for her to settle down because she used to bail me up all the time & she will bark at anyone whose walking out of the back door in the house still.
It took her 1 year to get used to be where she would sit on my lap while I am watching television or if I am lying on the bed she will jump up onto the bed & lie on it with me.
A couple of my aunties used to have silky terriers in her time,we prefer to own a terrier because they're a much more manageable dog which is good for children as well.
My dad had to give away a blue cattle dog 40 years ago because he jumped up & bit me on the arm so my auntie who was one of them whose friends were moving away had to give their Australian cross Terrier away to us when they moved !
Herding dogs nip/ bite if their charges don't do as they're told, your dad would have been better off giving away the disobedient one !
Yes Eliza was our Australian Silky Terrier, rescued from an Amish puppy mill. She was my wife's best friend, and we miss her every day ❤
How brilliant!!
Rust jacking ( to far away from tone ring) and metal debris on abs sensor magnets cause bizarre issues .
Excellent 👍
Not many people want to work on these big RVs
Generator, Inverter,HVAC , Water sewage Washer dryer etc etc
Would be a good business for you Ivan so much variant technology on these and most people who own such have the money to pay for proper diagnosis repairs .
I grew up as marine mechanic similar tech .
Rust will always be a problem in the northeast. That is a huge air gap for sure. GM has some issues too with their speed sensors getting crud buildup on them effecting the signal. Heck, probably all manufacturers do in some shape or form.
When a new problem shows up after maintenance, it's dang near assured that the new problem was induced by something that got previously touched. I've seen it many times. The "parts cannon" ABS module replacement was unfortunate.
Once again the PicoScope to the rescue.
Really important also is change out the brake fluid on these F- series rigs ! Forbid losing your brakes driving down a mountain ! Ive seen even 16,000 lb trucks do this a few times !
Bounder by Fleetwood. When I was working on those PITA overloaded hunks of fun, I called it Flounder by Beetwood. Yuck! So many of those over the years. Oversized beasts driven by old people. ABS seems sorta silly. Good luck locking up a wheel on that thing. Quite dangerous vehicles, IMO.
Also can be bearing issue.
There is nothing Ivan can't fix👊
Where did you get those adapter that converted the oscilloscope lead into multimeter leaves
@@tigertechpro7303 AESWAVE.COM
Two minutes in, I knew what it was. But then I worked for 30 years in Brake Engineering, mostly with Ford vehicles. LOL.
This one was right up your alley.
Very nice work as per usual, I see the owners enjoying your beautiful landscape like I would also. Do you use pico library to compare apples to apples? Thank you for another learning experience
do you have a set rate for diagnostic?
yes he does, not my business to go into it !but I've been there it's well worth it, actually enjoyed spending the money
The problem is clear, and obvious, a lot of rust on the sensor, and need to be changed even without any problem yet, don't take chances, but the other shop went after the ABS module, if I am the one who did the brake job I will.recommand strongly charging that rusty ABS sensors,
that is part of the brake system that can cause serious crashes if the signal is bad and cause the ABS to activate inaproberelly.
19:02 does it look like the frame is crapped out?
Common GM pickup ABS issues caused by rust buildup and raising the sensor off of the hub causing excessive tone ring gap. This causes the ABS to active when truck speeds were under 7MPH.
Budget diag tips for you who don't have an oscilloscope:
Listen to the signals using a (small battery powered) guitar amp, or any other type of amp with a high impedance input (like the gramophone input on a 50+ year old transistor radio).
Too wide gap would be noticeable as a difference in volume. Bad tone rings will be noticeable as beat frequency modulating the tone signal (like a wah-wah pedal, kind of sort of).
(Of course even the cheapest budget oscilloscopes for $20-$100 are better, but if a amp is what you happen to have you can get away using that instead)
Had a relative was thinking about putting a window on the storage door where the cats litter box is. the cat can go down from inside the rv. Thought that should get some strange looks from other cars. LOL
Looking at the video I could not see jack stands while you were working. As an old motor home owner that is a no no. I have worked under my MH with just the hydraulic jacks but after countless warnings I began using jack stands.
Ivan, you tried to analyse the problem from a voltage and resistance point of view. Some circuits work from a current point of view. I suggest you read up on the operation of a 20mA current loop. In the end your electrical tests proved nothing; it was the visual inspection which diagnosed the problem.
The owner is fortunate that you would work on his RV. I never liked it because of the lack of good service info, hard to find the correct parts and having the owners camping out in the service bay. I realized that it is their home on the road, but that is why there are rental cars and motels. I had to perform a transmission repair on a class C while the owners, with the blessings of the SM, sat in the next bay in folding chairs. Nice people, but come on! That was my last week at that shop.
My truck used to do this randomly. I did a full brake job and there was so much junk in the tone ring teeth it was basically round. Cleaned it and never happened again.
As soon as I saw it parked there I knew what the problem was. It's an RV.
Lehto just clicked next vid....
I was shocked how much trouble it is getting parts and info. I had to drive 125 miles to a bone yard just to get a transmission dipstick for a bus conversion. It is still a ford drive train, why do they care what is bolted to it. Needed the motor for the door as well, nada anywhere, then saw the city ran the mini busses so called them. "we don't sell parts." I know, but you have to buy parts from somewhere. Got their supplier and got the motor. turns out it was changed from a simple reverse polarity to a 3 wire signal.
So, added an extra DPDT relay to reverse the motor rather than run a signal wire through the chassis to the motor.
Watching this is giving me flash backs. Not good ones.
Nice work Ivan. Quick question though. Did you wind up reinstalling the original ABS motor pack? Since he didn't need it after all.
Rhode Island Rust belt, the the salty air along the Florida coastline.
Gonna get some rusty stuff.
Great example of why shops really need a Bore Scope and Oscilloscope.
In this case, a bore scope spotted the physical differences.
Gonna get me one.
Old school techs: oscilloscopes aren't that complicated... You put the signal on a screen. Two elements to adjust: (-1-) how fast the trace/sweep travels left to right, and (-2-) what amplitude the signal appears as.
The screen has LITTLE SQUARES and the scope front panel has controls for milliseconds or microseconds (etc.) per square for sweep horizontally and volts or millivolts (etc.) per square deflection vertically.
You can find scopes for LOTS of money and some for CHEAP. There's all sorts of classes in RUclips on how to use a scope. A VOM measures AC but can't tell you if it's sinewave, squarewave, trianglewave, etc. A VOM measures DC but won't see noise. YOU GOTTA HAVE A SCOPE.
BTW. .. some scopes AUTOMATICALLY adjust sweep and amplitude with resulting values DISPLAYED on the screen.
I was trained on one of the big Sun analyzer machines in the early 90s. Had the big swing arm with every cable and attachment imaginable, back in those days. We had a guy working on a motorhome that was pinging. Dude did heads, timing chain, distributor and wanted to keep throwing things at it until the owner got frustrated and hooked it to the Sun analyzer. It had a bad alternator. That was the only time in the years I worked for him that I saw him completely lose his s*@t. I learned from observation the value of a scope. ;)
@@farmermiyagi1338 i used the old sun monster ours had a gas analyzer in that same cabinet, it was a beast to move around a 2 bay garage , now i have a scan tool that fits in my front seat with my DVM and a good scope is in my future. I only do this part time now. But i still remember the Sun instructor showing us all of the options and the boss had us putting it on every car that came in for a tuneup then!
@@farmermiyagi1338 What does a bad alternator have to do with an engine pinging? I don't understand that. You/Anyone?
@@KStewart-th4sk All I know (this was over 30 years ago) was that there was a serious problem with the output signal from the alternator. The wave pattern on the scope was crazy. I would assume that it simply did not have enough power to drive the ignition system properly. Either way, a new alternator got rid of the ignition ping. Ivan might be able to explain it better than I can. I'm just a tech, he's the genius. ;)
@@johnchambers12 Oh yes, it had a gas analyzer. In the late 90s I came back here to central Arkansas, and got laughed at a lot for missing my gas analyzer. Now we have built in sensors for that though. If you can trust them to function properly that is.
Ivan has a ten ton floor jack?
It's soo funny how often basic mechanical systems are ignored and they go straight to the computer. Me mudder was sitting her watching this vid and giggling. Shes an ex truck and coach mechanic. She said problem arose after brake work, check work and abs sensor gap as they can get knocked around, sometimes they can be fixed but often replaced . Imagine a 75 year old woman calling it at start of vid