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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If you take the red covers off the lights you will find that the brake/turn filament in the faulty grounded bulb glows faintly when you brake, and the running lights glow brighter. What actually happens is the positive current comes to the brake filament and wants to go back to neutral. But it can't because the ground is not good on that socket. The current then goes through that running light filament in reverse, then across to the other running light filament and through that running light and to ground.
The running lights glow brighter than the brake/turn filament because you have three filaments all in series at that point. But you are feeding three filaments with a single 12 volt feed. The running light filaments are smaller than the brake filaments, and therefore cause a larger voltage drop across their filaments.
Take a wire from your battery negative and touch it to the metal side of the bulb holder, put on the turn signal, and everything will work fine.
And, I think you will find the loose connection is where the negative wire connects to the socket.
The running lights glow brighter than the brake/turn filament because you have three filaments all in series at that point. But you are feeding three filaments with a single 12 volt feed. The running light filaments are smaller than the brake filaments, and therefore cause a larger voltage drop across their filaments.
Take a wire from your battery negative and touch it to the metal side of the bulb holder, put on the turn signal, and everything will work fine.
And, I think you will find the loose connection is where the negative wire connects to the socket.
