7pin wiring problem. Please help!
I have a new to me travel trailer. I am having a few issues with the wiring. Let me list those and then I'll list what I have done so far. 1. When headlights are on, running lights are not. 2. Whe...
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YC 1 wrote:
If you TT plug is not molded you can take it apart. If you are careful you can plug it into the towing vehicle. That allows you to actually check the pins on the umbilical. This will eliminate the towing vehicle as a suspect.
You absolutely positively must have a proper ground. If you keep messing about without a good one you are going to add more problems by blowing fuses or worse.
For a novice, the test light is your friend. Even seasoned techs get busted using a voltmeter.
Do not ever rely on the tow hitch to be a good ground. Using a temporary jumper for a ground will let you sort things with confidence.
With the new long wire you buy connect it to the tow vehicle and connect your test light to that wire. If you can't get to the trailer plug easily just start at the TT light sockets and things should go smoothly.
Everything on the 7pin checked out with the light tester.
At the left tail light, there is power going to the bulb holder when head lights are on but no light. It’s a new bulb and I got it to light up when using my wife’s car battery. There is no flashing in the bulb holder when left signal is on.
At the right tail light, the bulb works with head lights but not right turn signal. Light tester doesn’t flash when touching bulb holder.
Running lights flash with right turn signal and running lights come on with brake lights.
The light tester was grounded at the tail lights.
What am I down to now? The junction box under the camper? I looked and it’s clean. No exposed wires. Looks ok.
The tail light assemblies?
