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Circuit Tester Kit

Circuit Tester Kit

Item # 40376
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Wiring 40376 - Circuit Tester,Test Light - Draw-Tite
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Circuit Tester Kit Lowest Prices for the best wiring from Draw-Tite. Circuit Tester Kit part number 40376 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
  • All Info
  • Reviews (18)
  • Q & A (4298)
  • Videos (2)
  • Photos
  • Why etrailer?

Draw-Tite Wiring - 40376

  • Tools for Wiring
  • Testers
  • Draw-Tite
  • Circuit Tester
  • Test Light

Circuit Tester Kit


Features:

  • Heavy-duty tester signals with a light and a buzzer
  • Tests low voltage up to 28 volts
  • Finds electrical shorts
  • Checks circuits from a distance
  • Checks polarity
  • Checks battery drain
  • Kit includes:
    • Alligator clip
    • Hook


40376 Circuit Tester Kit




California residents: click here


Video of Circuit Tester Kit

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




Video Transcript for Circuit Testing a Vehicle 4-Pole

Today Im going to show you how to test the functionality of a trailer four-way connectors. What youre going to need to do this is a circuit tester and a buddy in the drivers seat to operate the taillight functions. The first thing were going to test is the taillights themselves. Hit the taillights. (beeping) that means thats working. The next thing were going to test is the left blinker.

(beeping) That works. Then were going to test the brake light function on that side as well. So, hit the brakes. (beeping) That works. Then for the right blinker (beeping).

Now the right brake (beeping). Now we know that this four-way connector is functioning.


Customer Reviews

Circuit Tester Kit - 40376

Average Customer Rating:  5.0 out of 5 stars   (18 Customer Reviews)

Circuit Tester Kit

- 40376
by:

Easy to use voltage indicator. Flashes and beeps so you hear and see . Made the job so much easier. The coiled cord is really long and makes it very convenient. 776948



- 40376
by:

Purchased this to troubleshoot existing truck wiring and wiring I installed. Much more convenient than using my volt-ohm meter (VOM). 585992



- 40376
by:

Excellent service and attention to detail. I would highly recommend purchasing from etrailer. Prices are great and they have a wide selection of information that helps with the purchase decision. Very impressed. 551374



- 40376
by:

Excellent quality circuit tester. Can check battery drainage and troubleshoot wiring shorts. 498087



- 40376
by:

worked great for the purpose check wiring on trailer 422465



- 40376
by:

Well made, clear instructions and very useful for sorting out trailer wires. If you have several trailers and multiple towing vehicles this is real handy! 413164



- 40376
by:

Great product 376271


Comments
Great product
Kej263 - 05/04/2018

38106

- 40376
by:

Ordered several electrical connectors,wire and a wire tester .. all items came in good condition ,looking forward to using the tester as soon as I can I am sure it will do the job. 359795



- 40376
by:

I have placed several orders with e-trailer over time and keep returning. I have gotten ffast response on questions and all orders have been filled correctly an on time. 274120



- 40376
by:

Looks good 235043



- 40376
by:

This is my second Lisle circuit tester. I purchased to replace a unit I lost. These are very well made and worth the extra spend. The Customer Service from e-trailer is second to none and I'm a repeat customer due to the help these folks will render. 228513


Comments
Still works well and is still in great shape. Thanks for asking.
Scott P - 09/29/2016

21328

- 40376
by:

This circuit tester was worth every penny. The audio and light indicators took all the guesswork out of the wiring. It made it easy to identify turn signal and brake wires and I was able to test for proper functionality in my trailer contact once everything was installed. Highly recommended. 180242



- 40376
by:

This really is the ultimate circuit tester! The audible feature is a huge benefit when working alone and energizing a circuit remotely.... saved me multiple trips between truck cab and trailer tail lights! When working on trailer light circuits, this is a must have tool! 84638



- 40376
by:

This tester is well made and definitely worth the money. Makes troubleshooting wiring problems a breeze. 84363



- 40376
by:

High quality equipment! Thanks etrailer.com for the excellent service. 66038



- 40376
by:

Product were just explained. always a great job. i enjoy doing business with etrailer. 64106



- 40376
by:

Very nice tester. Heavier duty than the cheap ones you buy at local retail stores. I like the fact that it also has the audible tone along with the light. 33136



- 40376
by:

Great tester 31427


18
18

Ask the Experts about this Draw-Tite Wiring

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    To the best of our knowledge there is no plug-in adapter that will work on your 2015 Ford Transit T250. There should be a bundle of wires under the driver side dash that you can connect the adapter that you have picture to. Simply cut off the end that doesn't connect to your brake controller and use a circuit tester like part # 40376 to test for the following functions that you can splice your harness to: Blue - Brake Controller Output Black - 12V Power White - Ground Red - COLD Side...
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    The most likely cause for the RV backup lights to suddenly stay on when your towed vehicle is connected is corrosion in the RV connector. In a 7-way socket (please see photo) the 12V power contact at the 1:00 position and the backup light contact in the center can become bridged together. This can occur from corrosion on the inside of the connector or from trapped water or other foreign material that connects these two circuits. You can try an aerosol electrical contact cleaner like...
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  • No 12 Volt Power at 7-Way on a 2017 Ford F-350
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  • Why Would Trailer Brake Controller and Taillights Not Function on New Trailer
    Sounds like the new trailer needs to be grounded better or is just missing the ground all together. If all of the lights don't work and no brake controller the one thing they all have in common is the ground circuit. Most likely it's the main ground strap from the connector to the trailer frame. Make sure it's connected to a clean metal surface. I attached a couple help articles for you to check out.
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    It sounds like you have a bad ground or a short in your wiring somewhere. Another possibility is if you have a lot of lights on your trailer it could be causing the lights to overdraw. To find out what end the problem is on you will need to use a Circuit Tester # 40376 to test the different functions on the connector of your 1999 Jeep Cherokee. For your trailer side you will just need to use a different 12V source of power like the battery in your Jeep. Check to see if each function...
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  • Brake and Signal Lights Do Not Function When Head Lights are On
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  • Trailer Brake Controller Installation in 2017 Mercedes-Benz Sprinter 2500
    There is no plug-and-play brake controller harness for the 2017 Mercedes-Benz Sprinter 2500 so brake controller installation will be a hard-wire process. Under the driver's seat there should be a green plug. The wires to this plug can be tested with a circuit tester like # 40376 to confirm their function since vehicle wire colors are not always consistent. A brake controller like the Prodigy P2 # 90885 has 4 wires that require connection to the Sprinter. The black wire is 12V...
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    It definitely sounds to me like you have the connections in the 7-way connector on your vehicle connected to the wrong circuits. From your explanation I believe you may have the ground wire connected to the circuit that you are calling the taillight circuit. Use a circuit tester, item # 40376 if you need one, and the wiring diagram (see link) for the 7-way connector car end and you should be able to get the wiring connected properly. When looking at the wiring diagram remember that you...
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    The stop light switch wiring is located behind your brake pedal on your 2017 GMC Acadia. See the picture for a visual. If you are having trouble locating the wire you can use a Circuit Tester # 40376 to find out which wire sends a signal when the brake is depressed. You can use a Quick Splice Wire Connector # SWC501746-1 or a Butt Connector # DW05714 to connect the red wire from your brake controller to the stop light switch wire on your Acadia.
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    You will want to start off by checking all of the wiring on your 2016 Ram. Using a Circuit Tester, like part # 40376, you can test all of the pins on the 7-Way wiring harness at the rear bumper to make sure that they are all functioning properly. Since your brakes and brake lights are not working, I would make sure to look closely at the pins in the 3 o'clock, 5 o'clock, and 9 o'clock positions (see attached photo). If any of the pins are not sending a signal all the way to the wiring...
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    It sounds like you are on the right track. Your 2012 GMC Sierra does not have an OEM plug for installing a brake controller, but they did run the wires for you. We do not offer an adapter that would allow you to hard wire the Hayes Energizer III brake controller, but you do have the option of just cutting off the existing plug. You should be finding the correct group of wires under the left side of the instrument panel you see to the left of the steering column. There may very well...
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Info for this part was:

Expert Research:
Mike L
Expert Research:
Robert G
Expert Research:
Patrick B
Expert Research:
Michael H
Expert Research:
Jameson C
Expert Research:
John H
Expert Research:
Adam R
Expert Research:
Jeffrey L
Video Edited:
Zack K
Video Edited:
Andrew K
Updated by:
Sarah W
Updated by:
Alexander C

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