'03 Ranger w/OEM Trailer Wiring Issue

[MWalker]

Any help will be appreciated.

My Ranger right turn signal wiring fails to send a signal to the trailer.
I had a compromised wire with abraided insulation (green wire) and repaired that.

Is there a junction someplace in the factory wire harness that I can check?
The trailer plug harness goes into a wire bundle that would be tricky to troubleshoot.
Any good ideas on how to pinpoint the open circuit?

I can easily tap into the right turnsignal and run a dedicated wire, but I thought that there may be a junction or possible a fuse to check.

 

[rwenzing]

#1) The trailer turn signal/brake lights are fused separately from the truck's.

Dash fuse 3 = left trailer turn/stop
Dash fuse 7 = right trailer turn/stop

#2) The large, square connector under the truck directly below the driver seat it a potential problem area on all 99~2003 Rangers. It can fill with water/road salt/dirt causing shorts or opens in the circuits that go to the rear half of the truck. It is good PM on these years to open the connector, drain any water, inspect for corrosion and reassemble packed with dielectric grease.

 

[MWalker]

Thanks

rwenzing:

Thanks for your reply.
I knew that there had to be someone that could give me an answer to what I had suspected.

I will go did into the issues you mentioned.

Thanks