Heated Seats Won't Stay On

StevenZ · 12th January 2006, 06:19

Anyone got any ideas why 2000 M5 heated seats won't stay on? Push button and 3 lights come on for about 1 second and then go out (turns itself off). Same for both seats. Don't know if the seat heater is ever activated because its on for such a short time. Probably some controller because both seats went from working fine to this. Thanks!

slowcar · 12th January 2006, 06:33

Quote:

Originally Posted by StevenZ

Anyone got any ideas why 2000 M5 heated seats won't stay on? Push button and 3 lights come on for about 1 second and then go out (turns itself off). Same for both seats. Don't know if the seat heater is ever activated because its on for such a short time. Probably some controller because both seats went from working fine to this. Thanks!

I had the same thing the heated elements are shorting out. You can take apart and fix i just bought the lower leather which has the element glued into it. About $2000cdn. If i had to do it again i would try and repair myself first,
good luck. (mine was the r seat ) is your rear defrost or rear sunshade not working . Did you keep blowing the fuse?????

VancouverM · 12th January 2006, 06:35

Faulty switch module. The whole module with the Seat heater buttons, DSC btton, Sport button, Rear sunblind button, etc is one unit and likely has to be replaced.

Q: How do I know...

A: My 99 540 had the same problem.

Quote:

Originally Posted by StevenZ

Anyone got any ideas why 2000 M5 heated seats won't stay on? Push button and 3 lights come on for about 1 second and then go out (turns itself off). Same for both seats. Don't know if the seat heater is ever activated because its on for such a short time. Probably some controller because both seats went from working fine to this. Thanks!

Salty · 12th January 2006, 17:32

Quote:

Originally Posted by slowcar

I had the same thing the heated elements are shorting out. You can take apart and fix i just bought the lower leather which has the element glued into it. About $2000cdn. If i had to do it again i would try and repair myself first,
good luck. (mine was the r seat ) is your rear defrost or rear sunshade not working . Did you keep blowing the fuse?????

I see you have the Powerchip 93.
Where do you "fill 'er up"?

Ever use Husky 94 octane (10% ethanol)?

Anzir · 12th January 2006, 20:35

Same thing happened to mine a couple of years back and they replaced the whole seat (driver's seat) because the heating element was dead. It was under warranty then, and I got brand new leather... loved it! Wouldn't want to think about that now that the car is out of warranty.

jjc1843 · 12th January 2006, 23:33

Steven:

Hold on a second. Check the fuse for the seats.

Please.

StevenZ · 13th January 2006, 05:10

Quote:

Originally Posted by slowcar

I had the same thing the heated elements are shorting out. You can take apart and fix i just bought the lower leather which has the element glued into it. About $2000cdn. If i had to do it again i would try and repair myself first,
good luck. (mine was the r seat ) is your rear defrost or rear sunshade not working . Did you keep blowing the fuse?????

The fuse does not blow. I turn on either seat, i get 3 lights for about 1 second and the lights go off. I can do it again with the same result. If the fuse was out I assume it would never turn on. The fact that both seats are doing this and they use to work fine makes me think its not the elements. Is that right?

All air handling and rear defroster seem to work fine. THANKS!

StevenZ · 13th January 2006, 05:23

Quote:

Originally Posted by VancouverM

Faulty switch module. The whole module with the Seat heater buttons, DSC btton, Sport button, Rear sunblind button, etc is one unit and likely has to be replaced.

Q: How do I know...

A: My 99 540 had the same problem.

This is what I'm thinking - some controller board somewhere. So the controller electronics are built-in behind the switches as 1 box? What about the fact that some cars have options here and some don't. Mine doesn't have the sunshade or the active seats. They probably don't have a box for all configurations. I'm figuring some electronics box somewhere is the problem (in the dash, under the seats, under the hood?) You think it might be different on M5 than 540? THANKS!

VancouverM · 13th January 2006, 05:38

Quote:

Originally Posted by StevenZ

This is what I'm thinking - some controller board somewhere. So the controller electronics are built-in behind the switches as 1 box? What about the fact that some cars have options here and some don't. Mine doesn't have the sunshade or the active seats. They probably don't have a box for all configurations. I'm figuring some electronics box somewhere is the problem (in the dash, under the seats, under the hood?) You think it might be different on M5 than 540? THANKS!

I strongly doubt there is any difference (in that aspect) between two E39 cars! It may be possible to effect some repair- but I have no idea how practical that may be. In my case it was under warranty, so they simply replaced the whole module. I think there likely are various module configurations (or at least front panel button configurations) based on the options.

Good luck and let us know how it turns out in the end!

greg · 14th January 2006, 01:52

Quote:

Originally Posted by StevenZ

If the fuse was out I assume it would never turn on.

No! when the fuse is blown it behaves exactly as you describe - 3 lights for 1 second, then off. Happened to me - was only a fuse.