Select Your Vehicle
view cartView Cart
Only 7 Hours 24 Minutes Remaining

How to Test a 4-Way Trailer Wiring Harness Plug

Question:

I installed a 4 way connector to a 4 way-7way adaptor on my 2000 Mercury Mountianeer. When testing the connector, the test light flashed for the left and right turn signals, but when I ed the tester probe into the 3rd female plug.and applied the brakes, the test light does not go on. Am I doing it correctly ? I assume this is for the brakes. Can you provide some guidance.

asked by: Trubee K


Expert Reply:

You are testing correctly for the left and right turn signals, but the 3rd female plug you are testing is the taillight circuit. If you turn on the running lights you should get 12 volt power at the connection that the brown wire runs into.

To test the brake lights at the trailer connector you need to apply the brakes and test the connectors that the green and yellow wires go into. These are the same connections that you tested for the turn signals.

Trailer wiring combines the left turn/brake and right turn/brake signal for proper operation of the trailer lights. I have included a video on trailer connector testing for you to review.

The correct wiring for the 2000 Mercury Mountaineer is the T-One wiring harness, # 118345.

expert reply by: Bob G




Have a question for the experts? click here.


Products Referenced in This Question

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector


T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

ratingratingratingratingrating
4 reviews

118345

Retail: $69.84

Price:  $54.95

Product Summary:

Trailer Hitch Wiring
Powered Converter
Custom Fit

Product Specs:

4 Flat


more information        





Product Page this Question was Asked From

Quickee Circuit Tester


Quickee Circuit Tester

ratingratingratingratingrating
2 reviews

3808

Retail: $34.41

Price:  $24.95

Product Summary:

Tools for Wiring
Testers
Circuit Tester


more information        







    More Answers about Wiring




    Stay Connected


    Subscribe to our newsletter

    Email  

    privacy - we don't send unsolicited email





    Only 7 Hours 24 Minutes Remaining

    etrailer.com reviews etrailer.com reviews

    All images, layout and content copyright etrailer.com