Halp! I is burning!

[CorvallisBMW]

OK so I park my car in the driveway after driving home from work. I change clothes, do a few things and come back an hour later to run some errands. I open the door, and the car smells like it's burning. No smoke, no signs of any fire or anything out of place. It's a more acrid smell, like smoking hot electronics or something. I notice that the tach, mpg meter and trip computer are all dead, as are the power door locks. The driver's door lock is totally frozen and cannot be locked/unlocked. No smell under the hood or in the fuse/relay box, most of the odor seems to be coming out of the vents, and it gets MUCH stronger if I turn on the air recirculation. I am totally stumped, wtf would cause these symptoms? Do they share any common electrical parts that would cause this stuff? Everything else seems to be working perfectly.

[payney8]

i would start stripping your dash as obviously its bridging somewhere behind your dash. Find the source of the smoke and stop asap

[kellie]

Before you take anything apart, do you have any aftermarket electronics? I would start there. Any stereo, alarms or places where someone could have messed with the wiring. Especially if it was done recently.

[CorvallisBMW]

Before you take anything apart, do you have any aftermarket electronics? I would start there. Any stereo, alarms or places where someone could have messed with the wiring. Especially if it was done recently.

I haven't done any work on the car in months, i've been to busy with the vert. There is an aftermarket headunit, but it's been in there for 3+ years and never been an issue. I suppose something can still go wrong. I was just hoping to not have to tear apart the damn dashboard. Isn't there a nice, simple answer lol?

[CorvallisBMW]

update: drove home from the gf's house last night and the smell was gone, but all components mentioned above are still MIA, as is the driver's side trigger for the dome lights. The smell re-appeared slightly when I rolled down the windows, but then went away again a few minutes later. On the drive in to work today, same thing. I caught a faint wiff for a minute then it was gone. Do all of these compoments share any common harness or anything? I am stumped b/c they seem unrelated and are located in totally different places in the car.

[kellie]

Haha, it's never a simple answer when something deep within the dash is smoking!

I think the first thing to check (after checking fuses, obviously) would be the wiring for the headunit. It could have been positioned against something that has taken 3 years to rub through the insulation. You never know. Plus, while it's out, you can look around back there and possibly smell where it's coming from.

If any of your fuses are blown, that circuit is most likely the culprit. Check wires, check for burny smelling modules, etc.

I hate tracing stuff like this. I spent over a month trying to trace a similar problem in an E46. The speedo would intermittently die out, and it was all because of a pinched wire in the trunk. So good luck to you. If you have a manual with wiring diagrams, befriend it.

[kellie]

update: drove home from the gf's house last night and the smell was gone, but all components mentioned above are still MIA, as is the driver's side trigger for the dome lights. The smell re-appeared slightly when I rolled down the windows, but then went away again a few minutes later. On the drive in to work today, same thing. I caught a faint wiff for a minute then it was gone.

So maybe it is coming from under the hood after all? Or maybe whatever it was popped a fuse and isn't burning anymore?

Do all of these compoments share any common harness or anything? I am stumped b/c they seem unrelated and are located in totally different places in the car.

This is where your wiring diagram comes into play.

[smonkbmw]

*waiting for Lukes Lounge to respond*

[CorvallisBMW]

*waiting for Lukes Lounge to respond*

lol already sent him a pm...

[kellie]

I just checked some wiring diagrams, and couldn't find much linking everything. The only component they all seem to share is the fuse box (duh). Check fuse 10, 21 and 27, they control most of what isn't working in your car (cluster, OBC, interior lights and central locking).

[StereoInstaller1]

Shit, man...you have a BMW tech responding, what the hell do you need me for?

Drive down later this week if you dare, but I bet this link will help you immensely: http://wedophones.com/BMWManualsLead.htm

Luke

[CorvallisBMW]

I have to be in Salem on Sunday, so I may give you a call and arrange something if I can't figure it out.

[jlevie]

I'd say that it is imperative to pull the dash and carefully examine all of the wiring. There's a decent chance that something is causing excessive current flow through some circuit and overheating wires. Left unfixed you run the risk of an electrical fire behind the dash (worst case) or a lot of damage to the wriring harnesses.

[CorvallisBMW]

I will swap the seats in to the 'vert tonight so i can drive that while I try and hunt down the wiring issue in the 325iS. Hopefully it's not too bad, but I've never had to remove the dash before.

[mattdk318i]

all of those components have wires that run within 3 inches of the stereo. I smell a possible dead short behind the HU