1968 Overlander Running Light (Marker Light) Wiring Diagram or Routing Information
All lights work on my trailer except the running lights. I had no tail lights (or running lights) the other day until I chased down a short (I think) in the wiring. I removed the right tail light assembly and found 4 green wires that are connected together at that point. Three of the wires are larger and one is small. The smallest of the four would take significant current from a wire directly connected to the battery. I eliminated this wire from the group and my tail lights and license plate lights started to work. I assume these four wires are 1) the feed from the front, 2) one for left tail light and license plate light, 3) one for right tail light and 4) one to the rear upper clearance lights? The one for left stops off at the license plate light.
My vehicle (2014 ML 350) senses the extra current draw from the shorted wire and turns off the power to the tail light circuit and indicates "tail lamp out" on the dash display. There are no blown fuses his way, which is nice. This did make diagnostics difficult. Interestingly, it stated that the "left tail light" was out. Not certain how it could ever know that as they are all on one circuit?
I think I am correct in understanding that there are 13 lights on this circuit: 2 tail lights; 10 marker, clearance, or running lights (5 in front amber and 5 in the rear red); and the license plate light. These are all fed by the green wire in the 7-pin connector. Correct?
When I inspect the wiring at the access under the trailer where the 7 wires come in, I find a branch off the green wire that has been cut (or chewed) off about 6 inches from the connection. I cannot feel or see where this goes. I assume it feeds the front 5 running lights? Anyone know the sequence to the lights or where this wire goes from the access point?
I also assume the green wire that I disconnected at the right tail light back feeds the rear 5 running lights?
I replaced all running lights with LED light fixtures and have no power to any of them at this time.