Michael Benno

Every once and a while, the electrics in my '88 S4 driver seat stops working. Like this morning for instance. All buttons will be dead for the remainder of the drive and then after the car sits for a few hours the seat will work again. This seat has the memory presets.

I've had the seat out and the main electrical cable is in good condition and I cleaned and treated the connectors.

Anyone have any indication of where to start looking? Would this be result of an old relay at the main panel? Or does this have to do with the relays under the seat for the memory?

Mike

soontobered84

Fuses 20 & 21 may need to be cleaned
IIRC, there is no relay for the seats
Probably a dirty switch issue.

Chalkboss

I would spray Deoxit in the switches. Makes the dead live again. Worked for me.

James Bailey

Memory seats are far more complicated that regular seats....and yes relays boards etc. under the seat. To make it smart but also subject to alzheimers

MFranke

Not sure if you have same root cause, but I had similar symptoms on my 88. Cure was to reflow the solder on the boards under the seat. I noticed, on inspection, hairline cracks at some of the solder points. Has worked fine now for a few years since.

martinss

When the seat fails to move, is that in response to both the switches and the memory switches? If the seat fails to respond to both, you can likely rule out the switches themselves, and the memory module failure Mark mentions, dirty fuse or poor ground are likely.

Michael Benno

When the seat fails, all three control switches are dead, as well as, the memory function.

This only happens to the driver seat. For reference I removed and cleaned all three of the switch controllers with Diox last fall.

Looks like there is a fuse for each of the seats. I'll check and clean that tonight.

I'll do some research on the under seat controller

Michael Benno

Update... I checked the fuse and it was good.

I grabbed the wire harness and moved it around while holding the switches, BINGO, motors came back to life. Looks i have a bad harness or possibly where the wires connect to the seat. - winter project number 54. Sigh.