I used the loadpro when repairing construction rental equipment. Found lots of corroded wires, defective switches even defective brand new switches. Lots of people trash talk this tool here on RUclips. But this is my prefer way to test voltage drop. I made an extension lead so it could fit in tight spots.
Pretty nifty tool, I work on Semis and trailers. Cummins now recommends using this tool for testing during some diagnostics. I gotta say it's so much faster to use than dragging out the ole headlight bulb to put a load on the circuit
This is a very handy tool. I took Dan Sullivan’s electrical class around twenty years ago and used his first version of this tool for the first part of my career. Being a heavy equipment mechanic it helped me troubleshoot many corrosion problems. It looked like a set of test leads with a black box in the middle that had a red test button. I later upgraded to this newer set. It saved me a lot of time troubleshooting problems and to me is a must have in your tool kit.
It was a sad day when I realized that Dan Sullivan's company, original author of the LoadPro, went bankrupt a few years ago. I think marketing was the problem, since they did their best to obscure the simple design. As a tech, you must understand the design, otherwise you're working blind. It is a 25 ohm resistor, a switch, and a fuse in series. The multimeter measures the drop across that 25 ohm resistor, it usually measures 25.9 in mine, and it is good to check it before using the device to be sure it is working correctly. Knowing how the circuit inside works, you can easily understand what you are doing when measuring two readings, one with switch open, and a second with switch closed. With switch closed, current flows, and if extra line resistance is present the voltage measured by the meter will drop compared to the open circuit. A quick, simple way to do voltage drop testing in the real world.
Exactly! Just a clean way to toss in a resistor! I bought mine off of a tool truck many years ago that use to come to the shop where I was working. I had never head of it befoe. I also seen Napa sells a load pro, looks the same but it's blue.
Is it safe to use the Load Pro to test the fuel injector circuit in a gasoline vehicle? There is no injector pulse on all four injectors and the Nissan Sunny vehicle is cranking but not starting. I am looking forward for your reply.
@@kennydoolarchan9515 That would not be my first tool for the situation of no injector pulse on all four. I'd be checking engine codes, specifically looking for evidence that the cam and crank signals are getting to the PCM. The computer won't fire injectors if it doesn't get timing info. Control signals on that signal wire from the PCM aren't prone to voltage drop because the current is so small, it is typically a square wave. You can look for that square wave with a scope, but with it affecting all cylinders, the problem is likely not one of the wires. Don't forget the timing belt/chain, which makes the dance happen.
@@kennydoolarchan9515 Funny coincidence, the RUclips channel DiagnoseDan just posted a video today, titled "don't use a multimeter like this", outlining the complexity of diagnosing a no start when the immobilizer and computer aren't talking to each other. Different car, probably a very different system, but the basic principles are cogent. Even professionals struggle with the interplay of reflashing modules, communication between modules, and possibly broken wires. The more you know about these systems, the more humbling it becomes.
I think one more step that would have been good to show people so they understand it a little better is to put the meter leads on the wires while they're connected to the fan to demonstrate that the load of the fan causes voltage drop due to high resistance inside the circuit. before I knew this tool existed I got burned pretty bad on a job where a truck wouldn't run but showed that the ECM had good voltage. after a lot of tail chasing I back probed the connector and plugged it in and the load of the ECM caused the voltage to drop to nothing. If I had owned the loadpro at the time I could have checked static voltage, seen that the voltage went to nothing and known right then and there that i had high resistance.
That’s a pretty cool tool. I seen a tool a while back and I can’t remember what it was called but you looped it or “open clamped it” on a wire and could run it down the wire to find the break in it. It was used to check Christmas lights and the light on it would go out when it found the break in the wire. Of course you couldn’t run it down many vehicle wires like you could Christmas lights but I thought it would be very useful too. Between the tool I described and your load pro you shown, it would answer about any electrical questions. 👍
I read all the comments up to and including yours, because I was about to post the same thing. The author did not check the ground side from the connector to ground. He went straight to ground forgetting one half of the circuit! It’s a useful tool for sure!
In a real world scenario you would probably clip your ground lead to the frame or chassis of the vehicle. But your right, in this scenario you have to figure out which one, either the ground or power wire.
I don't really have a good answer other than trial and error. I suppose if one of them is corroded, it would probably be a good idea to replace them both.
@@1D10CRACY I was just curious. I have heard of this tool but have never seen a demonstration on it. I suppose running a temporary ground and or positive wire one at a time would probably be the only way to determine which wire was the issue.
@@Rngg01 You would start the test with both the positive and negative leads at the connection for the load with the load turned on, and if the voltage would drop low when you pressed the button, indicating a bad connection, you would then leave the positive lead on the load, and move the negative lead to the battery negative post, or a known good ground, an again check the circuit by pressing the button. If the voltage still drops low, the problem is on the power side, if the voltage however now stays high, the problem is on the ground side of the circuit.
Once again, terrific! I’ll be purchasing this. If you get a hankering, that battery/ alternator tester (for $69.99) would be really cool to demonstrate to us too! I would think you could find other uses, like on that electric car? Just my two cents, great video again!
“ANCEL BA301 6V 12V Battery Load Tester” from Amazon, sorry about that. It looks super interesting but I’m not very electrically savvy. I’m much better once you’ve demonstrated it to us. I don’t think I’m alone in that either. Eh, maybe in the future you’ll pick one up? Looks like it could help. Thanks again
Looks pretty interesting for sure! By what I can tell, that tester is sold under a handful of different names including Enusic, model BT01. As luck would have it, Banggood carries it as well and I have asked them to send me one for review and they said they would! So we shall take a look at it and see if its any good!
@@BlizzardOfOdds A quick and dirty review of the BT01, the exact same tester as the Ancel BA301, just a few dollars cheaper! ruclips.net/video/kLMzBckQ4yA/видео.html
A pro needs a go-to built-for-purpose tool to speed troubleshooting. Those of us DIY'ing can take the time to build the tools ourselves. For load testing, just raid a couple of incandescent duel-filament tail light bulbs, sockets, and a few inches of wire lead the next time you're at the junk yard. I have a collection of marker lights (0.2 amps), tail lights (0.5 and 2.0 amp), and headlights (55 and 65 watts). Wide-mouthed athletic sports drink bottles can be cut like a funnel to provide a hood to protect flesh and bulb from meeting while hot. Hot glue will anchor the bulb socket to the mouth of the funnel hood. For troubleshooting powers and grounds almost duplicating the Power Probe tool? Start with a quality 14 gauge, ten foot extension cord. Cut the female plug off keeping 4' or so of the cord attached. Strip back the external cord sheath 2' or so exposing the individual wires of power (black), ground (green), and common (white). Attach 30 amp alligator clip/clamps to the individual wires -- a red clamp for the black wire, the black clamp for the white wire, and a naked clamp for the green example. Use green heat shrink tubing to mark the ground clamp as, well, ground. What we now have is a female power cord end with alligator clip/clamps on the other end. Do the same thing to the male extension cord end but rather than use alligator clip/clamps, go with some kind of female banana socket. Keep the red, black, and green color scheme consistent and with continuity. So, how to use? The red and black conductors are rather obvious. The green conductor can be used for supplying a valid 5 volt reference if necessary. Here's the nice thing about this setup.. If one needs a longer reach, just plug in *any* regular extension cord for battery-to-back-of-trailer diagnosing. Be sure to leave each individual conductor with enough room to get an amp clamp around it.
The video would have been more informative had you explained what the reading should have been at 3:45 if there was no resistance in the circuit. For example, does that 3 volt reading represent voltage drop? Thanks
The voltage reaching the multimeter dropped from 12.8V down to 3V. That's a drop of 9.8V. This is the same as checking the voltage to the fan while the fan is hooked up and trying to run.
Completely isolate the wire, introduce battery voltage on one side of the wire, put load pro on the other side then connect the load pro negative lead to battery ground.
You could, and now you have to determine if there is an issue with the fan causing a voltage drop and not coming on, or if there is a broken wire, bad switch or something isn't capable of carrying the load. Same result on the meter, but not the same answer. You could use a test light to see if the circuit can carry a load!
As a technician, I find it a bit stupid that a technician would stop and recommend a component just because you see 12v on it's positive input. Part of the diagnostic process for electrical is checking for good power feed, checking operation of the component isolated from it's power and ground and then checking it's ground. I DID pick up a loadpro just to have a new tool in my toolbox, but it's going to sit beside my powerprobe which I use for actuating certain components. As an example, I had a 2013 Pilot with 3 door lock actuators that would not lock/unlock. Checked it's input and output and found them switching normally. So our control from the integrated relays of the MICU were good and doing their jobs. ($800 part), so the next thing I went to check is isolating the door lock actuators from network, providing them a known good ground and 12v for a brief second, enough to actuate them open and closed. No functionality. Dead door lock actuators confirmed since when isolated. Same thing with your fan example. Fan doesnt work but is receiving 12v? Let's isolate it, give it 12v and boom, it's spinning like normal. Now we can focus our gaze on the ground side of the system since we've confirmed we've got A) Good power and B) a functioning component. But it'll be fun trying to work the loadpro into my diagnostic routine since, hey, new tool because MUST HAVE NEW SHINY TOOLS.
Need to let people know to use the ground on the function then move to a good ground if load is good on a good ground it’s the ground wire that is bad but if load isn’t good on a good ground then it the voltage wire that is bad you still only load the voltage wire but this way you can tell which one is corroded or nearly broke
How would it know how much of a load to put on a given wire? What if it were a 1 amp draw vs a 20 amp draw device? Maybe it has a system inside that changes the load, but otherwise, I don't see how it would know how much load is right for a given wire.
@@1D10CRACY Assuming a bad wire, if the fan is good, wouldn’t it show the drop but not come on? If the fan is bad, wouldn’t it show the same voltage but not come on? Assuming a good wire if the fan doesn’t come on and you have voltage, then I’d guess a bad fan?
Your assumptions seem valid enough. Keep in mind everyone has their own techniques when troubleshooting. The load pro is just a tool that can sometimes help with speed, not a necessity.
Sure could. This company specializes in making those kind of tools that replace what we all had previously made. Another good one they carry is a relay tester, something anyone could make, but they sell a nice neat little package that puts a load on the contacts.
Interesting tool, but not needed. You have the circuit energized to test for proper voltage and ground at the component, never unplug a circuit looking for a voltage drop problem. you can not measure voltage drop on an open circuit. Leave the circuit plugged in and back probe the connector with a t pin and measure the voltage and again on the ground side.
I used the loadpro when repairing construction rental equipment. Found lots of corroded wires, defective switches even defective brand new switches. Lots of people trash talk this tool here on RUclips. But this is my prefer way to test voltage drop. I made an extension lead so it could fit in tight spots.
Does it work for 24v?
@@everytoolashammer9427 Yes it does upto 28.5volts. I believe there is a newer version that does upto apx 48 volts.
Pretty nifty tool, I work on Semis and trailers. Cummins now recommends using this tool for testing during some diagnostics. I gotta say it's so much faster to use than dragging out the ole headlight bulb to put a load on the circuit
This is a very handy tool. I took Dan Sullivan’s electrical class around twenty years ago and used his first version of this tool for the first part of my career. Being a heavy equipment mechanic it helped me troubleshoot many corrosion problems. It looked like a set of test leads with a black box in the middle that had a red test button. I later upgraded to this newer set. It saved me a lot of time troubleshooting problems and to me is a must have in your tool kit.
I’ve been using the loadpro for 10 plus years now and it’s invaluable.
I've never heard of this tool before today. Thanks for sharing!
Loadpro saved my rear end yesterday
It was a sad day when I realized that Dan Sullivan's company, original author of the LoadPro, went bankrupt a few years ago. I think marketing was the problem, since they did their best to obscure the simple design. As a tech, you must understand the design, otherwise you're working blind. It is a 25 ohm resistor, a switch, and a fuse in series. The multimeter measures the drop across that 25 ohm resistor, it usually measures 25.9 in mine, and it is good to check it before using the device to be sure it is working correctly. Knowing how the circuit inside works, you can easily understand what you are doing when measuring two readings, one with switch open, and a second with switch closed. With switch closed, current flows, and if extra line resistance is present the voltage measured by the meter will drop compared to the open circuit. A quick, simple way to do voltage drop testing in the real world.
Exactly! Just a clean way to toss in a resistor! I bought mine off of a tool truck many years ago that use to come to the shop where I was working. I had never head of it befoe. I also seen Napa sells a load pro, looks the same but it's blue.
Is it safe to use the Load Pro to test the fuel injector circuit in a gasoline vehicle? There is no injector pulse on all four injectors and the Nissan Sunny vehicle is cranking but not starting. I am looking forward for your reply.
@@kennydoolarchan9515 That would not be my first tool for the situation of no injector pulse on all four. I'd be checking engine codes, specifically looking for evidence that the cam and crank signals are getting to the PCM. The computer won't fire injectors if it doesn't get timing info. Control signals on that signal wire from the PCM aren't prone to voltage drop because the current is so small, it is typically a square wave. You can look for that square wave with a scope, but with it affecting all cylinders, the problem is likely not one of the wires. Don't forget the timing belt/chain, which makes the dance happen.
@@spelunkerd Thanks for replying. There were no error codes when the vehicle was scanned. The ECM was replaced but still the vehicle was not starting.
@@kennydoolarchan9515 Funny coincidence, the RUclips channel DiagnoseDan just posted a video today, titled "don't use a multimeter like this", outlining the complexity of diagnosing a no start when the immobilizer and computer aren't talking to each other. Different car, probably a very different system, but the basic principles are cogent. Even professionals struggle with the interplay of reflashing modules, communication between modules, and possibly broken wires. The more you know about these systems, the more humbling it becomes.
I think one more step that would have been good to show people so they understand it a little better is to put the meter leads on the wires while they're connected to the fan to demonstrate that the load of the fan causes voltage drop due to high resistance inside the circuit. before I knew this tool existed I got burned pretty bad on a job where a truck wouldn't run but showed that the ECM had good voltage. after a lot of tail chasing I back probed the connector and plugged it in and the load of the ECM caused the voltage to drop to nothing. If I had owned the loadpro at the time I could have checked static voltage, seen that the voltage went to nothing and known right then and there that i had high resistance.
That’s a pretty cool tool. I seen a tool a while back and I can’t remember what it was called but you looped it or “open clamped it” on a wire and could run it down the wire to find the break in it. It was used to check Christmas lights and the light on it would go out when it found the break in the wire. Of course you couldn’t run it down many vehicle wires like you could Christmas lights but I thought it would be very useful too. Between the tool I described and your load pro you shown, it would answer about any electrical questions. 👍
Maybe a clamp meter ?
@@akbychoice possibly, I’ll have to look it up. It was cool for sure
Good tool for trouble shooting the elusive electrical goblins. Thanks. The load pro AD in the link sounds like something out of the 60’s.
Btw, do your best and use the negative from the plug...... just so you can rule out a corroded neg wire ;)
I read all the comments up to and including yours, because I was about to post the same thing. The author did not check the ground side from the connector to ground. He went straight to ground forgetting one half of the circuit! It’s a useful tool for sure!
can you use this to diagnose wiring issues in the Hi speed CANBUS system?
Hi. Thanks for the video. Is a power probe the same thing? Regards
What if there’s a relay in the fan circuit? Would it have to be closed?
How u know is was the green wire if u tested it on the red wire.?
How did you determine if it was the ground or positive wire that was the problem? It a real scenario one would not know like you demonstrated.
In a real world scenario you would probably clip your ground lead to the frame or chassis of the vehicle. But your right, in this scenario you have to figure out which one, either the ground or power wire.
@@1D10CRACY So how would you utilize this tool to verify that?
I don't really have a good answer other than trial and error. I suppose if one of them is corroded, it would probably be a good idea to replace them both.
@@1D10CRACY I was just curious. I have heard of this tool but have never seen a demonstration on it. I suppose running a temporary ground and or positive wire one at a time would probably be the only way to determine which wire was the issue.
@@Rngg01 You would start the test with both the positive and negative leads at the connection for the load with the load turned on, and if the voltage would drop low when you pressed the button, indicating a bad connection, you would then leave the positive lead on the load, and move the negative lead to the battery negative post, or a known good ground, an again check the circuit by pressing the button. If the voltage still drops low, the problem is on the power side, if the voltage however now stays high, the problem is on the ground side of the circuit.
Nice demo, explained it well.
I have a question. Could you also check the red wire as well? Or is it that it would be the green wire (negative) only?
Once again, terrific! I’ll be purchasing this. If you get a hankering, that battery/ alternator tester (for $69.99) would be really cool to demonstrate to us too! I would think you could find other uses, like on that electric car? Just my two cents, great video again!
Thanks for the kind words! I can't seem to find the tester you are referring too, any chance you can reply with a link to it or maybe who makes it?
“ANCEL BA301 6V 12V Battery Load Tester” from Amazon, sorry about that. It looks super interesting but I’m not very electrically savvy. I’m much better once you’ve demonstrated it to us. I don’t think I’m alone in that either. Eh, maybe in the future you’ll pick one up? Looks like it could help. Thanks again
Looks pretty interesting for sure! By what I can tell, that tester is sold under a handful of different names including Enusic, model BT01. As luck would have it, Banggood carries it as well and I have asked them to send me one for review and they said they would! So we shall take a look at it and see if its any good!
Terrific! That would be great! I’ll be watching, thanks again!
@@BlizzardOfOdds A quick and dirty review of the BT01, the exact same tester as the Ancel BA301, just a few dollars cheaper! ruclips.net/video/kLMzBckQ4yA/видео.html
A pro needs a go-to built-for-purpose tool to speed troubleshooting. Those of us DIY'ing can take the time to build the tools ourselves.
For load testing, just raid a couple of incandescent duel-filament tail light bulbs, sockets, and a few inches of wire lead the next time you're at the junk yard. I have a collection of marker lights (0.2 amps), tail lights (0.5 and 2.0 amp), and headlights (55 and 65 watts). Wide-mouthed athletic sports drink bottles can be cut like a funnel to provide a hood to protect flesh and bulb from meeting while hot. Hot glue will anchor the bulb socket to the mouth of the funnel hood.
For troubleshooting powers and grounds almost duplicating the Power Probe tool?
Start with a quality 14 gauge, ten foot extension cord. Cut the female plug off keeping 4' or so of the cord attached. Strip back the external cord sheath 2' or so exposing the individual wires of power (black), ground (green), and common (white). Attach 30 amp alligator clip/clamps to the individual wires -- a red clamp for the black wire, the black clamp for the white wire, and a naked clamp for the green example. Use green heat shrink tubing to mark the ground clamp as, well, ground.
What we now have is a female power cord end with alligator clip/clamps on the other end.
Do the same thing to the male extension cord end but rather than use alligator clip/clamps, go with some kind of female banana socket. Keep the red, black, and green color scheme consistent and with continuity.
So, how to use? The red and black conductors are rather obvious. The green conductor can be used for supplying a valid 5 volt reference if necessary.
Here's the nice thing about this setup.. If one needs a longer reach, just plug in *any* regular extension cord for battery-to-back-of-trailer diagnosing.
Be sure to leave each individual conductor with enough room to get an amp clamp around it.
Thanks
so what would have been the reading when you put a load on the good wire? Would the voltage have been higher or lower than 3v?
Should be close to battery voltage if the wire is good
The video would have been more informative had you explained what the reading should have been at 3:45 if there was no resistance in the circuit. For example, does that 3 volt reading represent voltage drop? Thanks
The voltage reaching the multimeter dropped from 12.8V down to 3V. That's a drop of 9.8V.
This is the same as checking the voltage to the fan while the fan is hooked up and trying to run.
With corroded wires or a bad connection i can see a voltage drop on my multimeter. What am i missing here?
Can this be used for automotive (computer to sensor) wire testing?
Is this called voltage drop? Thank you
Sure is!
Wouldn't the load of the fan trying to draw current cause a voltage drop? Why cant you measure it in parallel?
Wouldn't a load drop test with a meter test the meter same thing positive to positive
Great vid well explained
What if your testing one specific wire from let’s say a sensor connector to the ECM connector? Where do you get the power for that circuit?
Completely isolate the wire, introduce battery voltage on one side of the wire, put load pro on the other side then connect the load pro negative lead to battery ground.
Just connect the dvom to the cables the same time as the fan and it will show the same result.
You could, and now you have to determine if there is an issue with the fan causing a voltage drop and not coming on, or if there is a broken wire, bad switch or something isn't capable of carrying the load. Same result on the meter, but not the same answer. You could use a test light to see if the circuit can carry a load!
As a technician, I find it a bit stupid that a technician would stop and recommend a component just because you see 12v on it's positive input. Part of the diagnostic process for electrical is checking for good power feed, checking operation of the component isolated from it's power and ground and then checking it's ground. I DID pick up a loadpro just to have a new tool in my toolbox, but it's going to sit beside my powerprobe which I use for actuating certain components.
As an example, I had a 2013 Pilot with 3 door lock actuators that would not lock/unlock. Checked it's input and output and found them switching normally. So our control from the integrated relays of the MICU were good and doing their jobs. ($800 part), so the next thing I went to check is isolating the door lock actuators from network, providing them a known good ground and 12v for a brief second, enough to actuate them open and closed. No functionality. Dead door lock actuators confirmed since when isolated. Same thing with your fan example. Fan doesnt work but is receiving 12v? Let's isolate it, give it 12v and boom, it's spinning like normal. Now we can focus our gaze on the ground side of the system since we've confirmed we've got A) Good power and B) a functioning component.
But it'll be fun trying to work the loadpro into my diagnostic routine since, hey, new tool because MUST HAVE NEW SHINY TOOLS.
It’s mostly meant to help figure out if you have high resistance in the circuit.
Need to let people know to use the ground on the function then move to a good ground if load is good on a good ground it’s the ground wire that is bad but if load isn’t good on a good ground then it the voltage wire that is bad you still only load the voltage wire but this way you can tell which one is corroded or nearly broke
How would it know how much of a load to put on a given wire? What if it were a 1 amp draw vs a 20 amp draw device? Maybe it has a system inside that changes the load, but otherwise, I don't see how it would know how much load is right for a given wire.
It doesn't need to know what kind of load is on the wire.
Cool tool. Mahalo for sharing! 😊🐒
I can see the tool has value. However, why wouldn’t in this particular simulation would you simply use the fan?
If you knew the fan was good, sure.
@@1D10CRACY Assuming a bad wire, if the fan is good, wouldn’t it show the drop but not come on? If the fan is bad, wouldn’t it show the same voltage but not come on? Assuming a good wire if the fan doesn’t come on and you have voltage, then I’d guess a bad fan?
Your assumptions seem valid enough. Keep in mind everyone has their own techniques when troubleshooting. The load pro is just a tool that can sometimes help with speed, not a necessity.
Just buy an electronic load or just a power resistor and a fuse.
Or you could make one. Plenty of options for sure. This is just another tool for the professional.
I would think some would test for voltage while the the wires were hooked to the fan to give them the same diagnosis. But the tool sells for a reason.
order a new fan and deal with the actual problem tomorrow, yolo
Or you can use a light bulb to simulate the load...much cheaper!!
Sure could. This company specializes in making those kind of tools that replace what we all had previously made. Another good one they carry is a relay tester, something anyone could make, but they sell a nice neat little package that puts a load on the contacts.
Interesting tool, but not needed. You have the circuit energized to test for proper voltage and ground at the component, never unplug a circuit looking for a voltage drop problem. you can not measure voltage drop on an open circuit. Leave the circuit plugged in and back probe the connector with a t pin and measure the voltage and again on the ground side.
Right, it's not needed, just another tool to speed up the trouble shooting process.
Just buy a test light
Different tool for a different job. You could make one of these for just a few dollars though.
Master lock is very uncommon.