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Cordless Circuit Tester

Cordless Circuit Tester

Item # PTW2979
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Performance Tool Electrical Tools - PTW2979

  • Testers
  • Circuit Tester
  • Performance Tool


  • Performance Tool cordless circuit tester detects voltage from 3v to 28v
  • Ground wire or clip is not required
  • Safe with ECMs, sensors, transducers, and the like
  • 2 Type "N" long-life batteries included
  • Buzzes and lights up if power is detected when the tester is grounded
  • Overall length: 6"

W2979 Cordless Circuit Tester




California residents: click here


Video of Cordless Circuit Tester

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Performance Tool Cordless Circuit Tester Review

Today we'll be taking a look at the Performance Tools Cordless Circuit Tester, part number PTW2979. Now this is going to be your Performance Tool Circuit Tester. It's going to be a handy little thing that's only about 6 inches long. It detects voltage from 3 volts all the way up to 28 volts. The nice thing about this is it's going to be cordless. It's going to use you as the ground so you're not going to need a wire or a clip with it.

It's going to be safe to use on ECMs, sensors, and transducers as well. It comes with 2 end type long term, long life batteries. Now here we'll go ahead and test it out. It does come with your probe as well, so if you like to just press that on to your wires and then probe your wires you can. If you have a four-pole like we do here, you can just remove that cover, hold it on the chrome or shiny part here. Then you're just going to touch the ground.

This is going to use you as a ground, so if we don't touch the ground, we're not going to get anything out of it. If we touch the ground with our finger with our freehand, you'll hear the audible beep as well as see the light flash. Now, if we let off that ground . So you'll know right away if you have a bad ground. That will do it for our review of the Performance Tools Cordless Circuit Tester, part number PTW2979..


Customer Reviews

Cordless Circuit Tester - PTW2979

Average Customer Rating:  4.5 out of 5 stars   (13 Customer Reviews)


by:

Not sure. Tried testing a 12v wire, had to go back to tried and true tester with pigtail & clamp, which gave me the result I was looking for. Maybe not doing something right, or I'm not enough negative polarity to give it a ground source. Inexpensive enough, I'll try again


Comments
The best suggestions that I can give you is to test it out on some different wiring. Once I know whether or not its working on some different wiring, then I can better assist you.
-- Etrailer Expert Katrina B - 07/25/2022


by:

I wasn't sure how this would work but I was pleasantly surprised. Handy tool to have.




by:

Everything was as advertised, and thank you Kaylyn R for your wonderful customer service. It took awhile to get everything installed, because of crazy events in the past year, but it all works great!




by:

I lost a $75 Snap-On circuit tester and bought this one to replace it. Not only is this tester easier to use but the cost is less than a third of the Snap-On version.




by:

Still using it on occasion. Have to watch the batteries.




by:

Great products and great people to deal with.




by:

OK




by:

Seems to work well, and my order was processed extremely fast. Great service!




by:

Delivery was as said and product as described.

Thanks




by:




by:

Works good as stated! Delivery was longer than expected.




by:




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13
13

See what our Experts say about this Performance Tool Electrical Tools



  • Troubleshooting Trailer Lights Not Working
    We don't have experience with OEM parts but I can give you some troubleshooting for your lights not working, though the Volvo dealer really should be able to solve this. I say that because you mentioned the trailer lights work on your other vehicles but not with your Volvo so we know it's on the vehicle side. That points to a harness issue or something else like a fuse. But the first thing you want to do is take a look at your grounds again - I know the dealer said they checked it but...
    view full answer...
  • Weak Trailer Brakes When Using The OEM Brake Controller
    If you connected a separate 12v source to the trailer and the brakes seem to work fine then it could be your factory brake controller itself. There has been issues with factory brake controllers on the Ram trucks. In order to connect an aftermarket brake controller to the Ram truck the factory brake controller has to be disabled by an authorized dealer or the two will interfere with each other. It sound as if the power wire coming from the factory brake controller has a weak spot or a short....
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  • Troubleshooting Brake Controller not Working Except With Manual Override
    I'm not sure which brake controller you purchased from us that you're referring to, though when a controller won't work except when using the manual override the issue is often on the red wire - the stop light wire - which sends a signal to the brake controller. You'll need to use circuit tester # PTW2979 to test the stop light switch wire, which is the wire that only gets power when you step on the brake pedal. If it does not have power then you likely have a blown fuse that you'll need...
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  • Interior Lights Are Not Working
    For just one side of your interior lights not working, it is likely a damaged wire or maybe a switch that is connecting the lights on one side has failed. You'll need to test the wires coming out of your switches with Circuit Tester # PTW2979. If the switch is bad and needs to be replaced I have added a link below to our selection of rocker switches for you.
    view full answer...
  • Connecting Trailer Lights to Wiring
    As nice is it would be, there isn't a universal type of color code so its not possible to tell you what wires connect to what, though often the yellow and red will be the turn signals and brake lights, brown is running lights and white is ground. In order to confirm that though, what you'll need to do is test each light with the Cordless Circuit Tester # PTW2979. Have your trailer connector plugged into your vehicle and have a helper activate the functions and you'll know which wire is...
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  • Brake Light & Anti-Brake Light on When Brake Controller Connected on 2000 Ford F-150
    There are only a couple of reasons I can think of why your brake light and anti-brake light might stay on when you hook up your brake controller. One is a bad ground, so you'll need to make sure the ground wires aren't loose, and are firmly attached to bare metal surfaces and free of any paint, dirt or corrosion. The only other issue may be that the brake controller was not wired correctly to the cold side of the stop light switch. I recommend double-checking that and using Cordless Circuit...
    view full answer...
  • 1997 Ford F-350 Trailer Brakes Locking Up When Harness Is Plugged In
    There are a few things you can do, to diagnose the problem. Start by disconnecting the trailer from your vehicle, then use a circuit tester # PTW2979 to test the connectors on the vehicle. Go through the functions with your tester and make sure everything is working. Inspect the connectors and connections, make sure there is not any rust or corrosion built up in these areas. If any of the pins show a constant 12 volts, and the corresponding pin on the trailer side goes to the brakes, that...
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  • Troubleshooting Brakes Always Engaged with Titan Electric-Over-Hydraulic Brake Actuator
    In order to troubleshoot this problem I would start by inspecting the connector on your trailer and your vehicle. It is possible they need to be cleaned and some corrosion is allowing the power to move to the brake wire, which would explain why the brakes are permanently engaged. If that does not fix it, I would recommend checking your 7-way at the back of the vehicle with a circuit tester like the # PTW2979. If you find that the pin for the brake controller has constant power then you...
    view full answer...
  • No Power to 12 Volt or Trailer Brakes on 2015 Ford F-350
    The first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation due to how easy it is to use - and test the connector on your vehicle after disconnecting it from your trailer. Check the wiring going...
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  • How to Troubleshoot no Running Lights on Trailer
    In order to troubleshoot what the issue is with your running lights there are a number of steps you will need to take, which I'll outline for you. The first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation...
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  • How to Troubleshoot Running Lights Not Working
    If the running lights are not working on your trailer, you have done the right thing by starting out checking the fuse, but there are a number of other steps you should take to troubleshoot. In order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation due to how easy it is to use - and test the connector on your vehicle after disconnecting it from your trailer....
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  • Why Are Trailer Running Lights Coming on When Brakes are Applied
    You are correct that the issue is on your trailer and based on what you are describing the circuits are somehow swapped when you installed your connector; unfortunately, I was unable to find your order number to see what you purchased from us for the install that may have caused this to happen. It is also possible that the brake and running light circuits shorted out and surged together. Either way, you will need to trace your wiring back, particularly at the running lights to see where...
    view full answer...
  • Can Performance Tool Wiring # PTW2979 be Used on More than Trailer Applications
    The Cordless Circuit Tester # PTW2979 is not limited to only trailer circuit testing. You can use it in basically any application that has voltage between 3 volt to 28 volt. I attached a review video for this for you to check out as well.
    view full answer...
  • Troubleshooting Trailer Lights When Connected to 2005 Jeep Grand Cherokee Limited
    The best way to troubleshoot trailer lights not wiring is to test each half of your towing rig separately. So for your 2005 Jeep Grand Cherokee you'll want to use a circuit tester like part # PTW2979 to ensure that each of the pins are sending power back to the various functions. Since it sounds like you already tested this your next step is to test the wiring on your trailer. You can test the trailer wiring by either plugging it up to another vehicle or by taking a 12V battery, grounding...
    view full answer...
    Image 1 for Image 2 for
  • Troubleshooting Tips for No Lights on Trailer
    So there's a number of potential reasons why your trailer lights may not be working, and I'll go over the troubleshooting steps you'll need to take in order to try and find the problem. The first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit...
    view full answer...
  • Only Running Lights Are Working on Trailer
    Since only the running lights are working on your trailer, the first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation due to how easy it is to use - and test the connector on your vehicle after...
    view full answer...
  • Troubleshooting Trailer Lights Not Working
    There's a number of general things to look for if your lights aren't working, which I'll go over for you. The first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order. If they are, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation due to how easy it is to use...
    view full answer...
  • Troubleshooting No Trailer Turn or Brake Lights with 2015 Ford F-250
    There are a number of possible reasons as to why the trailer turn and brake signals aren't working with your 2015 Ford F-250, and depending on how you're currently testing the lights the issue could either be on the truck or trailer side. To start I recommend using a circuit tester like # PTW2979 to test the 7-Way on your F-250. Test the brake/turn signal pins on the connector while you have a buddy flip on those functions in the cab. If you get power on the tester you know the problem...
    view full answer...
  • One Brake Locks Up on Trailer When Brakes Applied in Tow Vehicle
    One brake locking up on a trailer could be caused by a few different things. It would seem to me that the most likely culprit is that specific brake being out of adjustment. You'll want to adjust the assembly on that brake using the process shown in the attached video (check around the 4:40 mark). You want your brakes to only have a light drag when you turn the wheel by hand. The other possible cause of this would be that the brake magnets could be worn on one or more axles causing the...
    view full answer...
  • Troubleshooting Trailer Brakes In Over Load
    Since you recently replaced the brake controller you will want to do a quick check there. They have to be mounted in the direction of travel, cannot be tilted or turned side to side, and usually have to stay within a certain range pointed nose up or down. If that is off, it can cause the brake controller to perform erratically. Next I would try some testing. Disconnect the trailer from the vehicle, then use a circuit tester like # PTW2979 if needed to test the connector on the vehicle....
    view full answer...
  • Troubleshooting Trailer Lights Which are Not Working
    If your rear indicators are not working, it's almost certainly a poor ground, so the first thing to do is take a look at your ground connections to make sure they are attached to bare metal surfaces and free of any paint, dirt or corrosion. What is probably happening is the ground isn't strong enough for the load put on it and fixing this can resolve the issue. After that, refer to your owner's manual to locate any fuses or relays and ensure they are all there and in working order. If...
    view full answer...
  • Troubleshooting Trailer Lights Not Working
    While I'm not privy to what a guy did that may have caused the issue you're having, I can give you some troubleshooting steps to try, though you certainly did the right thing by checking your fuses. Next, in order to determine the specific problem you will need to purchase a circuit tester if you do not have one - the very handy Cordless Circuit Tester # PTW2979 would be my strong recommendation due to how easy it is to use - and test the connector on your vehicle after disconnecting it...
    view full answer...
  • Troubleshooting No Trailer Lights and Blinkers on Tow Vehicle Side
    Good job narrowing down the issue to your tow vehicle! If you have tried swapping out fuses you know work with the fuses that carry the stop/turn signals for your trailer then the next step is to figure out what is happening to the power. You need to start at the connector at the rear of your vehicle and using a circuit tester like part # PTW2979 you need to pierce the wiring at different locations to see where the signal stops. While you are doing this you need to look for places where...
    view full answer...
  • Side Marker Lights not Working on One Side of Trailer
    I do have ideas, which is that you have a ground problem or a short in your wiring. If the marker lights are okay on one side but not the other, your signals are getting to the trailer from the tow vehicle, so we can rule the tow vehicle's wiring out. A short or damaged jumper wire would be the most likely problem. I have added links to help articles on both trailer wiring and troubleshooting trailer wiring I recommend checking out.
    view full answer...


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Info for this part was:

Employee Jameson C
Expert Research:
Jameson C
Employee Jacob T
Video Edited:
Jacob T
Employee Dustin K
Video by:
Dustin K
Employee Wilson B
Updated by:
Wilson B
Employee Erin H
Updated by:
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Employee Jared G
Installed by:
Jared G
Employee Jacob W
Written by:
Jacob W

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