Trailer light tips and trouble shooting problems

[senkosam]

About three months ago I was having problems with some of my trailer lights working. My brother-in-law found what seemed to be causing the problem - a wire bundle that went to the plug located in the rear of the truck that had a short when raised and lowered. So, I took the truck to my local mechanic who found chewed wires under the main fuse box near the engine where a rodent had built a nest and used the wire's insullation. (I did notice the battery needed recharging once a week.)

Okay, after spending over $800 for the entire wire bundle to be replaced, I got the truck back and after a day or so the problem reoccured. Now I'm gettting steamed because I checked the trailer grounds, redid a few, replaced one bulb and a few wires. Plus I did a simple test that you can do for yourself if you're not sure which circuit is bad - left or right wires or bulbs):

Take a plug that fits the plug from the trailer and has four wires coming from it. Using a 12v battery, attach the ground to the negative post and touch the other three wires individually to the positive post. If the lights work, the problem is in the wires or plug at the truck. I did this test after I was told the the trailer wiring was screwed up but the lights were all bright as could be when I did the test! (I took a picture at night and showed the mechanic.)

So after months of dicking around with a know-it-all mechanic that did not check the rear wire harness or plug adapter I informed him was defective and then charged me for something that did not fix the problem, the truck is back to the shop. That's four round trips back to the shop (gas mileage is about 15 mpg) plus me buying a new wiring kit and bulbs that weren't needed! Worst of all was not being able to fish on the prime days the truck was in the shop that I had taken time off for!

I better not be given a bill!!!!

By the way, the fuse box for the trailer for GM trucks is located in the cab left of the steering wheel, NOT ONLY near the motor as was thought by the FIRST mechanic that worked on the truck.

It's one thing to depend on a computer program to diagnose a problem; it's another to have the the innate ability to trouble shoot and properly repair without one THE FIRST TIME!