BimmerFest BMW Forum banner
1 - 20 of 32 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter · #1 · (Edited)
I've owned my E39 for 5 months and 5K miles. After replacing battery, alternator and final stage resistor, I've been pretty much free of electrical gremlins.

Until Friday.

My driver seat adjustment, and the steering column adjustment have stopped working (steering column is in the full upright "entry-exit" position). Passenger seat adjustment works fine. To be clear: The driver's seat does not respond at all (it's not a single motor issue). Same with the steering column.

I checked the fuses in the glove compartment, and battery voltage at rest is OK at 12.7v.

Also, tonight my central locking got a bit wacky, but I was able to get it to lock properly.

I'm going to disconnect the battery tomorrow morning for a while to see if it will clear the memory/reset the CPU's, etc.

Any ideas?

Thanks in advance.

--
2000 E39 528i 5 Spd
Sport package - BMW Schwarz
Currently stock...
 

·
Registered
Joined
·
12,691 Posts
What condition is the plastic seat cover (the part that goes around the base of your driver's seat)? If it has broken away at one of both of the points where it screws into the seat...the electrical connector may be getting pushed out and causing you to lose seat and steering wheel functions.

Blubee has done several exhaustive threads about this VERY common issue. Just click the search button at the very top of the page (in the black band) and do an advance search using "seat switch" or "seat cover" as the search word...and also select "BLUEBEE" (for USER NAME)...and search specfically on the e39 forum.

Do the above, and you can't miss Bluebee's threads on this topic that is full of pics and info. Again, check the electrical harness for the large seat switch (the rectangular seat button) because it's the one that controls the seat & steering wheel...it would be the first thing I'd check to make sure it's not the culprit.

Good luck.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #3 ·
Thanks for the quick reply QSilver7! I'll search for that thread and test out that fix this morning.
 

·
Seek to understand,^Value
Joined
·
25,199 Posts

·
Registered
Joined
·
15 Posts
Discussion Starter · #5 ·
Thanks bluebee! I'll be reading the thread and taking a look at my car in a few.

Any value to disconnecting the battery to make things "reset"?
 

·
Seek to understand,^Value
Joined
·
25,199 Posts
Any value to disconnecting the battery to make things "reset"?
In my case, the harness connector was disconnected from the seat control module, so, no, in my situation, resetting the battery would have done nothing useful.

It's easy enough for you to try though ... and report back your observations so we all benefit.

 

·
Registered
Joined
·
15 Posts
Discussion Starter · #7 ·
Thanks for the advice. It was right on target!

The socket of my seat switch was broken in a way that looks almost exactly like your photo. I removed the plastic cover and put the switch back on so the seat/steering column would work yesterday.

Today I will repair the plastic socket housing. I'm going to try plastic solvent cement. If the plastic responds, this will weld the plastic together (the socket housing will have to be held in a vise). Some plastics don't respond to solvent cement though.

I also have 3M black epoxy (for electronic potting) that works very well for these repairs, cures super hard, and is black too. I may try to wrap something around the socket housing to add reinforcement.

The 3M black epoxy is very liquid and will go into small crevices. It does cure very slowly, so the part needs to go in an oven. I would heat the part to about 150º F, similar to what it has to endure every day parked in the sun. This will cure the epoxy in about an hour rather than 24 hours (approximate times from memory).

I used the same 3M black epoxy to bond my master key back together after changing the rechargeable battery.

I have these things at my workplace so I'm going to do the repair there.
 

·
Seek to understand,^Value
Joined
·
25,199 Posts
The socket of my seat switch was broken in a way that looks almost exactly like your photo ... I'm going to try plastic solvent cement.
Before and after pictures would be nice (so we all benefit).

Also, let us know what solvents worked and which didn't (again, so we expand our tribal knowledge).
 

·
Registered
Joined
·
12,691 Posts
...The socket of my seat switch was broken in a way that looks almost exactly like your photo...
Yep, they always tend to break in a similar pattern...that's why I asked if your seat cover was loose on either end. If so, the problem will return regardless of using a product to try to fix the broken "neck" where the harness plugs into the switch.

If the plastic seat cover is not in the correct position, when you exit and enter the vehicle, it puts undue pressure on the harness which eventually breaks off the "neck" of the switch. Fix the cover (buy a new one) or the problem will probably return.

Here's mine...I bet the part highlighted in the orange box broke similar to yours and Bluebee's. :(


Did you loose the little white lever that locks the harness into the switch, too?

 

·
Registered
Joined
·
15 Posts
Discussion Starter · #10 ·
I repaired the connector plug housing on the seat switch today using 3M DP 270 black epoxy (the plastic on the seat switch housing did not respond to the plastic solvent cement). The broken plastic part had to be held in place with a vise. I cured the epoxy in an oven.

The seat lower side cover did have the plastic broken where the front torx socket screw holds it to the seat. This plastic seems to be styrene and the plastic cement worked well. It is now drying overnight, held together with a small vise.

If the plastic weld repair on the seat cover looks good tomorrow, I will bond a washer to it with epoxy. This should make it strong enough to last for a while.

I did take pictures of the repair process. I'll post them when I get a chance (please share some photo posting tips). I'll probably start a new thread about seat switch repair, so it will be easily found in a search.

Thanks for your help... you guys saved me hours of electrical troubleshooting. Hopefully I can contribute something back with these plastic repair techniques.
 

·
Seek to understand,^Value
Joined
·
25,199 Posts
I repaired the connector plug ... using 3M DP 270 black epoxy ... I'll post pictures when I get a chance (please share some photo posting tips).
Wonderful. That's the quid pro quo here. We all learn by helping. Those worth helping, and those who give back in return, get helped even more!

To post a picture, here's my simple DIY:
- Shrinking is required; shrink to about 640x480 & about 100KB (Irfanview Windows freeware does both of these tasks quite nicely in batch mode for any set of pictures).
- Annotating the pics is easy but takes time so it's not required; the best Windows annotation freeware is Paint.NET IMHO.
- Press the "Manage Attachments" button to upload.
 

·
Thebizzy.com
Joined
·
6,429 Posts
Man I'm having major steering wheel issues and now seats on both sides are acting up. One side of them adjusting but not the other so like I'll be sitting sideways. It's starting to piss me off. Q Missed you at the E38 ATL meet this weekend buddy. We had a great time at Cody's!! :thumbup:
 

·
Seek to understand,^Value
Joined
·
25,199 Posts
One side of them adjusting but not the other so like I'll be sitting sideways.
I don't have experience with that but it's called, I think, seat twist.

Dunno the canonical threads on that, but a search for "seat twist" revealed quite a few candidates ...

This one post, by ElwoodBlues, seems to be a good starting point.

 

·
Thebizzy.com
Joined
·
6,429 Posts
Thanks Bluebee. Interesting info if nothing else. Seems like my baby is falling apart around me lately. At least it runs great and no CEL!
 

·
Thebizzy.com
Joined
·
6,429 Posts
Wow just read that thread too. Thanks again. Damn this repair is no joke and it needs to be done to both seats. I think I'll just start scouring the local junkyards to see if I can find some cheap and replace.
 

·
Registered
Joined
·
15 Posts
Discussion Starter · #16 ·
Seat Switch Repair DIY

OK, guys (and gals!)... as promised, I have posted my "black epoxy seat switch repair DIY"

http://www.bimmerfest.com/forums/showthread.php?t=465255&referrerid=195804

You guys saved me a lot of time by sending me straight to the source of my problem. Hopefully this little procedure will be found useful.

My seat is back together and working just fine.
 

·
Seek to understand,^Value
Joined
·
25,199 Posts

·
Registered
Joined
·
15,320 Posts
Thanks QSilver7 and bluebee for the beautiful pictures!

I just found out both the SW adjustment and my driver's seat do not move!

If my memory is good, a few days ago....I kneel on my L knee on the driver seat to reach across and reach stuff in pass seat!
This almost knocked off the connector. I will find out soon but 99% sure I knocked the switch off!
I plan to zip tie it back. Will post some pics soon.

The Lesson to learn: DO NOT KNEEL with your knees on the driver seat (or vice versa, on the pass seat trying to reach opposite side.)!!!
 

·
Registered
Joined
·
12,691 Posts
Ooo...I hope it's something simple. And I forbid kneeling on the seats for a totally different reason...especially the front passenger seat....and that's because I don't want the wires in the occupancy mat to break.

I suspect that many that have gotten this SRS fault issue is due to people putting a knee in the seat...which concentrates all of their weight into one smaller location instead of spreading it over the entire mat as would be if one was "sitting" in the seat.

The above is only a theory...I have no data to back it up...just a hunch. :D
 

·
Seek to understand,^Value
Joined
·
25,199 Posts
I forbid kneeling on the seats
I recently watched a small kid get into an E39 by using the seat cover as a stepping stool.

I'll bet a lot of seat covers break off from that!

To cn90, if you're lucky, the connector just fell off. If you're like most of us, the black plastic buttress around the connector broke. Mine has been shoved back, even though it's broken, and has been working ever since.

Here's the threads for details:
- seat covers that don't protect switches for both the steering wheel tilt & driver's seat control (1) (2) (3) (4) (5) (6) (7)
 
1 - 20 of 32 Posts
Top