Power seat control module diagnosis/repair

[Mad Cow]

Has anybody tried to repair a power seat control module? My original driver's side was intermittent for a while and then totally died, the relays just clicked rapidly and sparked a bit when trying to move any of the seat motors. Tested the motors by applying 12v to them through the 12 pin connector and they're fine. Recently tried a module from a junkyard car and each motor only moves in one direction (forward and up for seat bottom, and un-recline for the seat back), I hear the relay click and interior lights dim a bit going the other way. I could try finding another module, but I'd rather try making this one work at least temporarily. I don't even know where to start, what kind of fault would break the reversing circuit for all the motors? I get that it's using dual relays meant for switching polarity to drive a motor, but how does it control 4 motors with 3 relay pairs? Or should I just swap over the passenger side module, if that's possible?

[Firebug]

Sounds like you might have a short to ground. I would disconnect the harness from the module and the seat switch then do a resistance check on each wire. While your checking wiggle the harness in the door jam they tend to break there with the repeated flexing when you open and close the door.

[Mad Cow]

A short in the wiring that goes to the memory switches? I never thought of that, the memory switch did work the one time I accidentally pressed it but it could be intermittent. I'll check that out, thanks.

[chris86vw]

The memory module can be removed if you want to take any of that out of the loop and just test the function of the seat switches and the motors.

Have my seats down to finally swap the memory module over to my a6 seats from the stock allroad seats.. but they are trapped between the wall and a car right now or I'd snap some pics.