Why Would Trailer Wiring Install Potentially Cause Lighting of Trailer to be Dim When Tested

Question:

This connected well and works but gives a dim display on test and on trailer lights, I went back and checked and reset the ground but still dimmer than when connected to my truck, any ideas.

asked by: Nelson W

Expert Reply:

Did you check with the engine running or just with key in on position? You'd want to have the engine running so that the alternator is supplying maximum voltage to the wiring circuits of your vehicle. That will make the trailer lighting much brighter.

expert reply by: Jameson C