Also keep in mind that the trailer lights are on circuits that are separate from the lights on the truck body. Separate trailer fuses for left brake, right brake, and running lights.
Possible trailer plug/adaptor problem
- Thread starter OR VietVet
- Start date
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OP
OP
Before I start poking around, where are the fuses for the trailer lights? In the same fuse box as the truck lights? I was gonna look at this yesterday but grilling took over. With the Xfinity and Cup races on today, it is not gonna happen today either. I will be working on my neighbor's trailer this week and will look at the lights problem then, when I have a trailer to hook up to and verify everything. Thanks, @Fless
In the underhood fusebox. The underside of the lid should have the diagram for the layout.
OP
OP
@Fless, I did find a blown 15 amp mini fuse that was marked as TRL PARK and replaced it. I also found an ok 15 amp TRL BU. Replaced the blown fuse and now have brake lights and headlight/park lights and left turn signal but still no right turn signal. The right turn signal has been the constant, as the one that does not work. Both of the 7 pin adaptor plug ins have the same, no right turn signal problem. Further digging required.
OP
OP
Dug in a little deeper today. The back of the trailer wire 7 pin plug in is loaded with crap and the junction block has a crack in it. Luckily my Tahoe lights all work. I ordered in a replacement Genuine GM junction block. It was located directly above the tailpipe about a foot up on the inside of the body. Looks to have a clip that you stab in and then a bolt at other side. I also ordered an ACD 7 pin harness assembly and I ordered a Curt bayonet mount assembly for the harness. It does not bolt into place, it stabs thru the mount hole and you turn it and it locks into place. Will be doing a complete cleaning and re-tension of all plug in connections at the block.
I should have offered my OE 7-blade bayonet mount connector (no harness); I replaced mine a while back with a PnP Hopkins. Well, if anyone needs one, it's available for the cost of the ride.
you can always test the pin's on the trailer connector with a meter at any time to verify operation, a trailer is not necessary
there are diagrams online that show which pin is which, left/right/brake/power, etc
there are diagrams online that show which pin is which, left/right/brake/power, etc
OP
OP
The flip cover on the 7 pin has the wires/connections all identified. You should know by now that I don't piece things together. I just replace parts that don't meet my standards.
Update? Wondering if this fixed the issue.
OP
OP
I got the new GM junction block and installed it. I cleaned each wire/connector and used dielectric grease during the reinstall and did find another blown 10 amp fuse at the fuse block at driver's side of the dash and now all works as should. Sorry for the delay on the results.
