REAL MAN TRUCKWORKS & SURVIVAL

VEHICLES, CAMPERS, and BOATS => General Vehicle Related Discussion => Topic started by: stewie on April 20, 2018, 10:44:52 PM

Title: driver side trailer lights not working (GMC Sierra)
Post by: stewie on April 20, 2018, 10:44:52 PM: I did a bunch of searching on the issue and some are saying a short others a fuse, but i cannot find in the fuse box where left/right brake & signal lights are. i just see lights and brakes.

Am I looking in the wrong spot? i dont think it's the trailer because my suburban was recently towing it and all the lights worked.
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: stewie on April 20, 2018, 11:28:43 PM: its dark out now so i went out and was able to troubleshoot better. all the lights go on but the left light wont flash when i put on the turn signal. it will also not brighten when i apply the brake.
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: KensAuto on April 21, 2018, 12:24:57 AM: The fuse is inside, by the driver's end of dash. They have separate fuses for left and right turn lights.

Scratch that...my '12, 3/4 ton says it's #3 fuse, under the hood fuse box(https://uploads.tapatalk-cdn.com/20180421/1fcad084a3f1df80f6dd4be44dea6b9e.jpg)
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: stewie on April 21, 2018, 08:49:40 AM: just checked all the fuses.

i took the left light assembly off and inspected it. it gives a faint pulsing when i turn the hazards/turn signal on, but only for a few seconds. when i unloack truck it lights up, but when i lock (pulsating) it doesn't.

is s a bad light assembly?
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: KensAuto on April 21, 2018, 12:06:33 PM: I would say a bad ground on that bulb, but not if it works fine on the burb. Try wiggling the plug?

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Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: Bob Smith on April 21, 2018, 12:17:19 PM: Try the truck plug-in with another trailer to be sure what you are trying to fix. Like Ken, I would be checking the truck plug-in for corrosion or bad wiring.
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: stewie on April 22, 2018, 08:47:27 AM: Quote from: KensAuto on April 21, 2018, 12:06:33 PM
I would say a bad ground on that bulb, but not if it works fine on the burb. Try wiggling the plug?

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did all that. i got a new light unit. ill tinker with it during the week so i have no plans to move that trailer for at least 2 weeks. i will also check the connections on the truck.
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: KensAuto on April 22, 2018, 11:37:23 AM: A test light would sure help.

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Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: stewie on April 22, 2018, 01:37:38 PM: Quote from: KensAuto on April 22, 2018, 11:37:23 AM
A test light would sure help.

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roger.
Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: TexasRedNeck on April 22, 2018, 05:43:22 PM: And a VOM

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Title: Re: driver side trailer lights not working (GMC Sierra)
Post by: stewie on April 22, 2018, 08:59:43 PM: oddly enough the parking assist wont turn back on after i disconnected the trailer. it may still think one is attached. This leads me to believe the adapter in the rear is shot.