Hi everyone,
My driver power seat stop working, and the dealer found "grounds were way above normal levels; suspect corrosion under driver seat". It seems to me that car it's not as old (2006) for such corrosion. Does someone know the way to fix it without removing driver's seat and carpet ???
zdravkod

 

The seat is actually pretty easy to remove. It is secured by 4 large bolts under plastic covers. There are some electrical connectors which are pretty straight forward. You probably should disconnect the battery. Per VADIS, leave the car off for about 5 minutes before removing the negative terminal. When re-connecting, the key should be in the "II" position. (don't know why but that is what it says). The car may run a little rough at first until it acclimates.

I am puzzled by the diagnosis. Does the car show signs of corrosion elsewhere?
Stan

 

Hi Stan,
I managed to remove driver seat before I read your message. And I didn't find signs of corrosion. Thanks for the suggestion.
On two supplying cables under the seat, I measured 0.82V; supposed they should read zero. I tried to trace those two cables, it's impossible, there are many of them, whole harness, but no sign of corrosion.
Now you are suggesting disconnecting battery, and then connecting again, with the key in the "II" position. Do you think, after that, the power seat will operate again ? Will there be some harm to the radio or other components afterwards??
Zdravko

 

Disconnecting the battery was a precaution for removing the seat. I doubt that it will fix anything. Where were you measuring (between what two points)?

 

Under the seat, there is cable bundle, which ends with a plug for different purposes. There is orange cable (12.5 V between it and body); then left of it there are two tinier cables and I measured (0.82 V between it and body) on each of them respectively. I guess they should read ZERO, for only two needs to be live- seat movements and heating. Is it possible that somewhere those two cables are coroded and power from orange cable pentrates into them??

 

What are the colors of the other 2 wires that measured 0.82V?

Did you happen to check all the grounds under the hood on the strut towers to make sure that they are tight and making good electrical connection.

I have the wire diagrams for the car but it is too big to post.
Stan

 

Perhaps this might help.
Stan

 

Hi Stan,
thanks for the power seat electrical diagram. I will measure voltage and resistance accordingly in next couple days, and see what I will get. I will also check all the groundast under the hood.
Zdravko

 

Hi Stan,
when I opened connection on the side of the driver' seat, first I found different cable number and color, other then in the scheme you sent it: there where 7 (seven) incoming cables and color doesn't mach. (I attached simple drawings with real colors). It might be for the S40 drawing is for 2004, and my V50 is 2006. But I measured only one cable with 12.5 V, and the rest read zero. Now I am wandering, do I have to measure at least one more live, if I compare it with S40 scheme (top one, connected with F86)??

Zdravko

 

Hi,
finally, mechanic at Adria Auto Centre in Ottawa, ON solved the problem.
One supplying wire which goes from fuse box to computer and then to the seat was cut, due the corrosion. To find which wire, mechanic removed trim in front of fuse box, then under the steering wheel. He removed seat and carpet under it. He went trough and checked each wire individually and finally he found the broken one. It took him some 4, 5 h to do that.
I would rather have manual seat in my next car.
Thanks Stan (AutoNaut) for your help and diagram.
Zdravko

 

Hey, glad you got it fixed and glad you found a real mechanic who can use his head to solve a problem. If it were just me driving my car I would be fine with manual seats. Since my wife also drives the car it is nice to have the seat memories.
Stan