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Trailer light pigtail - LCD's - FYI

693 views 0 replies 1 participant last post by  haccpguy 
#1 ·
As an FYI:

I was having problems with my trailer lights. Whenever the headlights or parking lights were on the turn/brake lights would also energize. If the headlights were off, the turn, brake lights worked fine. In other words, on the 4 prong plug ( ground, running, L Turn, R Turn) both L and R Turns would show 15V when the headlights turned on.

I took it in to the dealer who replaced and checked all the relays and fuses.
It turned out to be the aftermarket LED's I was using in my trucks rear tail lights. When he replaced them with regular bulbs the problem vanished.
I would not have believed it if I did not see it myself.

Apparently the trucks computers were sensing too low a resistance in the lights and defaulting to an all on situation.

Luckily I have a very cool dealership ( Mod friendly too! - I do not have to return to stock for maintenance like this) and he did not charge me for the tech work.

Moral of the story: If you are having weird issues with your trailer lights and have aftermarket LED's installed in your truck, try replacing them with factory incandescence and see if that solves the problem.
 
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