Electric problems and water in the rear footwells

[infamousbutcher]

I've got a 2005 E53 3.0d Sport with 83k miles.  It's been well maintained and with the exception of the drivers door handle carrier failure (which I fixed thanks to these forums) it's been very reliable in the 18 months I've owned it.

Until last night!  I went out to the car last night and it wouldn't start, behaving like a flat battery.  The AA attended and got the car started.  They checked the battery and the alternator and both I'm told were fine but the battery needed a charge.

However, immediately the car had various intermittent electrical problems. 

• Self Levelling Inactive warning message showing
• Central locking (button on the console and remote) not working
• Hazard Warning Light switching on when the ignition is turned (??!!)
• Seat Memory not working
• Heated seats not working

I've read that low battery voltage can cause weird electrical problems so I took the battery out and charged it overnight.

When I reconnected the battery the electrical problems were still there.

With further investigation I've found that my rear footwells (especially on the passenger side) are soaking wet.

So after spending much of the day on forums the closest to my problem I've found was on an E39 thread but it seemed pretty similar.  They had found that the wet carpet had corroded a fuse box under the front passenger seat and affected a wiring loom also under the passenger seat.

My plan over the weekend is to remove the front passenger seat and hopefully find the affected fuse box/wiring.

Does anyone have any thoughts or advice they can offer?

I haven't been able to find any guides to removing the seats or carpets but will look again for these online tomorrow.

Then once the electrics are fixed I'll start on finding and fixing my leak!

Any help/advice/pointers gratefully received.  My skill level is little more than novice (but I've been given confidence to attempt things partly through this forum and partly through watching Wheeler Dealers!)


Thanks.


Ross

[davesavage257]

I had wet rear carpets in mine this winter, and found it was the membranes behind the door cards, no longer sealed to the door.  Ran sealant all round the edges, stuck the membranes back, dried out the carpets and all is good.
As for the electrics, did you try a reset with the battery disconnected, holding the positive lead to the negative lead of the car for 30secs before reconnecting the battery.  I've heard that can help.

Sent from my D5503 using Tapatalk

[infamousbutcher]

I've now stripped out the rear seats, rear carpet section and front seats and have the carpets drying.  I've charged the battery again overnight to be on the safe side.  But other than the wet carpets there's no sign of water or corrosion elsewhere.

I should also say I've checked fuses both front and rear.

I've started it again this morning and the problems seem to still be there (altho' I haven't put the seats back in yet  so can't check the memory problem).

So I think I have a computer or bus problem somewhere.

Dave - I tried holding the battery leads together - thanks for the tip - but it didn't help.

Is there a single bus or management unit that controls these functions?

I've got a mechanic coming round later to stick a computer on it so we'll see what that throws up.

Again, any thoughts or pointers VERY gratefully received.


Ross.

[Steamyrotter]

Central body module (ZKE i think) has most of them..
However the hazards are on the Light Control Module (LCM) therefore unlikely to be a single module fault.
Seats i believe have their own module also..

It may, or may not, be an issue with the ignition switch module itself as this can throw some seriously strange anomalies into the mix (Google it and look on XOutpost)
Could be an easy thing to discount if nothing else.

Silly question, have you read the codes and reset them, then seen if they comeback??
They could be hangovers from a previous fault..??

[infamousbutcher]

Thanks Steamy.

I ordered a Scanner at the weekend and it's due for delivery tomorrow.  I'll see what that says.

When I plugged the battery back in on Saturday after a full charge the central locking started working again - with the button on the central console and with the key in the drivers lock (but still nothing form the remote).  Then after I'd pulled the car out of the garage put the seats back in then drove round the block they stopped again.

Same with the seat memory - died again after driving round the block.

I was thinking the GM3 could be in transport mode after the charge and the AA jump start??  Does that sound sensible?

Oh, and now my air bag light is on 'cosI started up the car to move it into the garage out of the rain without the seats connected! D'oh!  :-[

[Steamyrotter]

[quote="infamousbutcher"]
I was thinking the GM3 could be in transport mode after the charge and the AA jump start??  Does that sound sensible?
[/quote]

Possible but doesnt explain it working for a bit then stopping...

Search on here for pairing the key remotes to the car.
That might be one less issue to worry about.....

[infamousbutcher]

I connected up the Scanner tonight and it could only communicate with a handful of modules.

I reckon I'm beaten.  Something seems to be taking one or more of the buses down.

I'm going to get it booked into an Indy and see what they say.

Ross.

[Steamyrotter]

Probably a good idea for starters.
As you are new to these then at least they could corroborate your experience and results.

That should give you more confidence to delve deeper later on if you are getting the same as them..

[infamousbutcher]

Update - finally fixed (I think!) after being off the road for 6 weeks and a bill of £1100.

It turns out it was the air bag control module that had become faulty.

It took it to the local Indy but they eventually sent it to the BMW Main Dealer for diagnosis and repair.

Lesson learned!

Time for a newer car with Main Dealer warranty I think.