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Cordless Circuit Tester

Cordless Circuit Tester

Item # PTW2979
Retail:$39.08
Our Price: $20.35
You Save: 48%
Electrical Tools
Shipping Weight: 0.19 lbs
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  • Reviews (13)
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  • Videos (1)
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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 Satisfaction Score:


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

Etrailer Expert

Katrina B.

7/25/2022

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.



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:

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:

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



by:

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



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:

OK



by:

Great products and great people to deal with.



by:

Works good as stated! Delivery was longer than expected.



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13
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See what our Experts say about this Performance Tool Electrical Tools

  • Trailer Blinker and Turn Signals Only Work on One Side
    Since it sounds like you were trying to match up colors during your install I believe you are correct that you wired it incorrectly. Although there are common wiring colors, there are no rules saying that everything has to be wired using any specific colors. This goes for both vehicle and trailer side. If you connect wire colors instead of checking their functions you could end up with an incorrect wiring system. What I recommend doing is using a Circuit Tester # PTW2979 to test the function...
    view full answer...
  • Troubleshooting a 2001 Ford F-350 with 6-Way Not Recognizing Trailer Brakes
    The interesting thing about 6-ways is that there are two different ways they can be wired with the difference being the brake output circuit and 12v power circuit being swapped. I recommend testing the center pin and the 10:00 pin with a Circuit Tester # PTW2979 and seeing which one has power when the brakes a depressed. If it is the center pin, then you will want to swap the center pin and 10:00 pin. If this is not the case, then you may have an issue in your wiring or grounds.
    view full answer...
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  • Trailer Lighting is Getting Power But Lights are Not Working When Connected to 2008 Chevy Silverado
    If you are getting power to the connector on your 2008 Chevrolet Silverado and you have tested and found that there is power on the wires that go to the lights themselves, then it sounds like you have a short somewhere - most likely near the lights. You can verify this by using an alternate power source, like the battery from your Chevy, and test the different functions on your trailer connector. You can also check the connector on both your Chevy and your trailer to make sure there is...
    view full answer...
  • Trailer Brakes Have Power But Do Not Work
    In order to find out what the issue is, we will run through some troubleshooting to properly deduce the problem. Start by cutting the blue wire on your brake controller and check for continuity with a circuit tester like # PTW2979 when you apply the manual override or when you depress the brake pedal. If that checks out, then reconnect the blue wire and move to the truck side trailer connector. Ensure the connector is clean and free of rust, dirt, or corrosion. At this time you need to...
    view full answer...
  • Troubleshooting Trailer Lights Working After Trailer Tongue is Moved Up and Down
    If you are having to wiggle wires around before they start to work on your trailer then you definitely have a short or a bad ground somewhere on your tow vehicle or trailer. It can also mean that you have corrosion somewhere on your wiring as well. Start off by checking the connectors and make sure that they don't have any corrosion or debris built up. You can determine which one it is by using a Circuit Tester # PTW2979 to test each of the functions on the connector for your tow vehicle....
    view full answer...
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  • 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...
  • What Circuit Does Red Wire of Brake Controller Attach To
    I would hammer a little harder on what circuit they attached the red wire to of the brake controller. It was supposed to attach to a circuit that only has voltage when the brakes are applied. If they attached it to a random circuit and didn't verify it had voltage that would definitely be why.
    view full answer...
  • Why Is My Brake Controller Running Hot And Locking Up Overnight
    It sounds like your brake pin has constant 12V power and it should not. You will need a circuit tester, such as the Cordless Circuit Tester, part # PTW2979, so you can check the voltage on the brake output pin on your 7-way connector. This pin should be at the 5 o' Clock position on your 7-way connector. My guess is when you test that connector you will find that it reads 12V, but it should not read anything if the brake controller is not activated. I have attached a diagram that shows...
    view full answer...
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  • Interior Lights Not Working on a 1998 Sooner Horse Trailer
    If all of the other functions on your trailer are working correctly, then you most likely have a short or a bad ground on the wiring that your interior lights are connected to. You can trace it all the way to the trailer connector on your horse trailer and look for any places where the wire might be bent, damaged, corroded, or exposed and replace it or fix it. Another way to test and see if that is the problem is to test the pin on your tow vehicle side connector that is used for 12V...
    view full answer...
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  • Determining Wire Functions on Truck and Trailer with Non-Standard Colors
    When adding a trailer wiring harness to a truck or trailer it's always best to make connections based on function, not color. This is especially the case in situations like yours where non-standard wire colors are used. On your truck you can use a circuit tester like # PTW2979 to test the wires you mentioned while you have a buddy run through the lighting functions in the cab. You will just need to find which wire gets power with each corresponding light function (running lights, brake...
    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....
    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 Turn Signal Not Working on Trailer
    I can give you some troubleshooting steps to take to try and find out what is wrong with your turn signal. 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 into your harness from your tail lights to see if the turn...
    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...
    view full answer...
  • Troubleshooting Trailer Lights not Working Properly
    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...
    view full answer...
  • Troubleshooting Tail Light Wiring On a 2012 Palomino Stampede Travel Trailer
    While I wish I could tell you exactly what color wire goes to each function there is no standard wiring guide required to be used for trailer manufacturers and the manufacturers of the wiring/lights. Looking at the wiring you do have I see the trailer has white, red, and green on the left side with white brown and green on the right. It would most likely be safe to assume the red and brown wires operate the turn signals and brake lights for each side of the trailer. The green is most likely...
    view full answer...
  • Troubleshooting Trailer Wiring
    I'm not sure what you are using or what vehicle you have so I'll have to give you general troubleshooting tips. 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...
    view full answer...
  • How to Determine Wire Functions of Vehicle 7-Way
    To determine how to wire any connector you will need to determine the function of each wire with a circuit tester as there is no universal color code. I recommend the very handy Cordless Circuit Tester # PTW2979 due to how easy it is to use. Once you find their functions you can match them to your 7-way, and the accompanying diagram shows the connections for the different style of 7-ways. I have added a link to a help article on trailer wiring I very strongly recommend reading.
    view full answer...
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  • How to Determine What Wire Functions are on 2007 Ford F-250
    If you take a look at the accompanying diagram, which is from our linked help article on wiring, you can see the common wire colors used by manufacturers. I want to stress that the only way to know for certain the functions of each wire on the 7-way of your 2007 Ford F-250 is to use a circuit tester such as # PTW2979. There are a couple reasons for this, notably because there is not a standard color for 7-ways in regards to function, and also because wiring may have been changed out in...
    view full answer...
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  • 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...
  • Do Trailer Wiring Colors Matter For Turn Signals/Tail Lights
    So with trailer wiring, the color codes aren't going to matter; all that is required is to know the functionality of the trailer wires. If you know what they are you're set, but the one thing you will want to do is verify the functions using a circuit tester such as # PTW2979. I have added some links below to help articles on trailer wiring which I recommend checking out as well.
    view full answer...
  • Determining Trailer Connector Functions
    Wire colors don't mean anything as there is no standard so it's impossible to tell you what wires do what. The only way to determine which wires will connect to the different trailer connectors you have is to identify each by function using the Circuit Tester # PTW2979.
    view full answer...
  • Both Trailer Turn Signals Blink at the Same Time
    This is normally related to a bad ground connection somewhere. Make sure the main trailer connector ground and the grounds for each of the lights are all connected to clean and corrosion free bare metal surfaces. Also make sure that the vehicle side and trailer side connectors are clean and free of corrosion. If you are using a 4-Way harness then these are the most common issues. If you have a 4-Way but it has 5 wires coming out then this is a wishbone harness and it will have the running...
    view full answer...
  • Troubleshooting Erratic Trailer Braking with New Tekonsha Prodigy P3 Controller Installed
    I first recommend checking the Tekonsha Prodigy P3 Brake Controller # 90195 itself. You can check the output voltage at the rear of the controller by cutting the blue wire 5 to 6 inches behind the controller. Test the wire with a multimeter like # PTW2979 when activating the brake controller. When you read the output voltage coming from the controller, there should be between 12-13 volts when activated. If there is a fluctuation or a large drop or spike in the voltage, then the issue may...
    view full answer...

Do you have a question about this Electrical Tool?


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:
Erin H
Employee Jared G
Installed by:
Jared G
Employee Jacob W
Written by:
Jacob W

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