Turn signal help

[Kyzera]

I have a 2008 GMC Sierra 1500 and the other night, the passenger side turn signal lit up solid and won’t go off. I’ve changed the bulbs and the turn signal switch. That hasn’t worked. Anybody know what else I can try???

[Jsdirt]

Sounds like a flasher relay that has welded its contacts together. I didn't think these vehicles had flasher relays anymore- thought the BCM controlled all of that. If that's the case, then there's a short to ground in somewhere in that turn signal's wiring.

[Kyzera]

Do I just need to follow the wires and look for any that are exposed or stuck together?

[Jsdirt]

 Yeah, a visual inspection of everything never hurts. Before you get too deep, check EVERY dual-filament bulb and make sure a filament didn't bridge between the running filament and brake / turn filament. I know you said you changed the bulbs, but I'm not certain you meant EVERY bulb. You'll only have to change any that have broken filaments.

Edited November 19, 2021 by Jsdirt

[Kyzera]

I had some that were blown, so I’ll replace those tomorrow. It’s only the passenger side that is staying lit all the time. I’ve been trying to figure it out for a couple days now. I just leave my battery disconnected 

[Jsdirt]

So it's staying lit even with the switch off and key out? If so, that's an odd one. In that case you could have a seemingly unrelated issue with the BCM, like a blown maxi fuse or a missing ground that's causing some weird symptoms. The joys of modern automobiles ...

 

A dead short is also still possible. 

[buddy brown]

I'm going through this something on a 08 yukon xl denali.  Its my left turn signal.  Replaced the switch still stays on but my blinker all work fine. Has me lost. I've been chasing ground but no luck yet.

[Kyzera]

My dad and I ended up following one of the wires. With the truck off, it was hot all the way to the fuse box, so I think maybe something in the body control module is messed up. But we just cut that wire for now, I’m just without a front turn signal on the passenger side lol