Drivers side heated seat failed, and now my fog lights don't work.

[MikeOD]

I'm out of warranty on my car (48K miles) and wondering if anyone has had any similar issues. My fog lights stopped working this morning (both of them and the bulbs aren't dead). The indicator light on the dash comes on normally, so I think the switch is ok.

My drivers side heated seat stopped working last week...I don't really care because it's summer time, but I want to fix it. The indicator on the button comes on, and I hear a relay click like I always did, but then after a few moments, the light on the button turns off. The passenger side heats fine.

I would like to troubleshoot this stuff myself because as I said, I'm out of warranty, and I don't like letting other people work on my cars anyways, but I'm not sure where to look first. Any advice?

[Easton091]

First thing to do is check fuse 35 and 50 in the underhood fuse block. If both of those are good, should be some sort of shorted/pinched wire.

[MikeOD]

I think it might be a low voltage issue...seems to be lower than usual.

[MikeOD]

Originally Posted by Easton091

First thing to do is check fuse 35 and 50 in the underhood fuse block. If both of those are good, should be some sort of shorted/pinched wire.

I think the BCM is bad. The fuses are all fine, the wiring harnesses are all fine too...every wire to the fog lights has proper continuity on the ohm meter, as does every wire to the drivers seat, and like I said, the passenger side seat works...very frustrating to diagnose an issue like this.

Anybody know if you can buy a BCM ready to go from GM, or do they have to install it so that they can program it for the cars options?

[lsgun]

My driver side heated seat just started the same thing last week. Any ideas yet? I think my drls are fine though

[MikeOD]

I figured it out...I had a bit of water in one of the fogs and it blew both bulbs and I just didn't realize it...they didn't look blown to me at first...but they are...stupid things are EXPENSIVE.

My heated seat, I haven't figured out yet, but I went through the FSM...the BCM doesn't control it, and it's got a very nice diagnostic procedure to determine which component in the seats or heater controller could be at fault...I'll get to it soon.

[TStko]

did you ever find out what the issue was, this appears to be very common after i've done research majority of the time drivers side and now mine just started doing the exact same thing. after around 1 full minute it shuts down but passenger side works perfect

[MikeOD]

I never did...I haven't been home much all summer so I haven't had a chance to take anything apart to fix it.

[rivenwolf]

if the light only stays on for about a min and turns off then one of the 2 heater elements have gone bad. the resistance in the element will be off. GM diag makes you test all the wiring and module but If you go straight to the connecters for the elements and test you will find the problem. the back element just has just 2 pins. the bottom element you need to test pins 3 and 4. the seat will need to be room temp and usally see between .5 and 2 ohms on each element.

[MikeOD]

Can I replace the elements without replacing the leather?

[DJ_BigC]

You element is most likely pooched, common issue on vehicles with heated seats.

Yes you can replace the element without replacing the leather, but the leather cover has to be removed to replace it, which means you'll probably needs new headrest guides if you break the retaining tabs when you take them out and you'll need 18 hog rings (small ones) if my memory serves me correctly to reinstall the leather cover.

Seeing as how you understand how to test wiring, you'll have to find the 2 heating element wires/terminals at the main drivers seat connector (under the seat, I'm pretty sure its 2 wires/terminals) and test for resistance or continuity through the heating element. If your meter shows/reads O/L your element is open and needs to be replaced, Have someone sitting in the seat for one test and have the seat empty for another test, because with someone in or out it might cause the element to have continuity or no continuity, either way in or out you want resistance/continuity. If your serious about diagnosing this, send me a PM and I'll send you the GM schematic for heated seats.

[rivenwolf]

everything dj said is right but I don't ever need the headrest guides as I don't take them out just flip the leather up to replace element. you will need some hog rings and hog ring pliers to install. a really good pair of side cutters will also help with removal. Cheap side cutters don't cut the hog rings very easily. the same will be needed for the bottom if that is the element that is out.

[MikeOD]

I'm taking the car off the road for the winter very soon...want to try to enjoy it for 1 or 2 more weekends...after that I'll pull the seat out and figure this out.

[don0fthedead]

rivenwolf, or anyone really,
If you came up with a DIY for this, I'm sure TONS of people would appreciate it. It sounds like it might be pretty time consuming, but if you did it, and were ever in my area - the beers are all on me.