RH Trailer light always on - factory tow pkg 2018 Tacoma

Suddenly on a trip the right side trailer light is always on. I sourced it all the way to the under hood fuse box. The only way to turn off the light is by pulling the 25 amp towing fuse (circled in yellow). In the multi wire plug shown by the white arrow, the light blue wire is always hot, all the way back to the trailer plug, same small gauge blue wire going into the back of the plug, which is the Right stop/turn post on the plug. As the light is always full on, the brake and turn signal does not register. All else works fine, as the factory tow package run in parallel separate from truck lights. I pulled all trailer related relays and it does not go out. Swapped the horn and tow tail relay, as they are the same, no change. Looks like it’s one of you or the dealer as my only hope

 

The TOWING side "control" is integrated into the combination meter.(Gauges & such) It's not a part that can be removed & replaced like all earlier versions of the Tacoma. Most likely you have a burnt trace which would require a new combination meter. If you had a buddy with same year & version Tacoma, you could swap and test before purchasing a replacement.

 

Thank you for this! I will see where it takes me, and report back with anything that I might learn.

 

Hi Caribe You were correct again. I pulled the combo meter and verified that the bad right rear trailer signal was emanating from it. I could see not any visible evidence of trace damage etc. that would explain the behavior. I ordered a factory part online (Toyota Parts Overstock) for $275 and the order appeared to go through. Then I was told "Due to federal regulations governing vehicle mileage, we can't sell the instrument cluster over the website. Your order has been cancelled and the hold on your funds has been released." I took it to the dealer and for $99 they told me the same thing you did, and that it would be $875 to replace the combo meter; and "it might not fix it, but it appears that it will". I am considering "clipping" the currently misbehaving right rear factory package source wire, and wiring my back right tail on the truck directly to the matching wire entering the trailer plug. What do you think?

 

I'd advise against that. You'd loose what the trailer component module does (combine Turn & Stop).
Any other dealers near you?

 

I'm talking to a shop tomorrow that says they can do it, we will see how much. Thanks!

 

I have a drawing of parts that can be substitute the failed circuit. It would an external by-pass, much cheaper than a new Combination meter and the work to change and certify a new Combination meter. Plus you don't cut any OEM wires. It's an intercept harness, you'd be using the 25 amp towing circuit wire and the towing wires added to a 2nd Gen Towing converter.

 

Nice! Set me up. Thanks!