96 Spider Power Seat not working?

Hi Roger.
I think the relais for the non working seat is gone. Indeed the power signal to the seats is given by the roof ECU (via relais).
According to my research the relais used in the roof ECU are Siemens (now Tyco) V23081-C1061-A303. These relais are directly soldered onto the circuit board, so no real "plug and play".
Before trying to replace the relay I would recommended to check the cable harness between ECU and the non working seat.
Thomas

 

About one year ago I ordered a pair as a reserve for my F355.

I only received one V23081-C1061-A303 and one V23081-C1059-A303.
I was told V23081-C1059-A303 is a compatible number but I did not get a proof that this is correct.

 

"Resolve the potentiometer"? Just to clarify, Roger, is it only the passenger seat you are having problems with?

According to a 1994 diagram, all seat power/control goes through the roof ECU, even when the seats are operated manually (I assume the later models work this way, too).

Do you have no power to the passenger seat potentiometer and the motor?

 

So the potentiometer is not getting power either? My roof ECU diagram shows separate power outputs for the motor and potentiometer. I thought perhaps that the potentiometer should have power to it all the time, not just when the motor was activated.

Roof ECU pinout

 

ouch... Good luck, Roger... I believe those units are unobtainium...

By the way, would you have a picture of the other side of the board (just curious)? Thanks.

Cheers.

 

By the way, the diagram shows a direct connection between the window switches and the roof control unit. I'm not sure if this is correct for later model cars. I think the window switches send signals to the Window Control Unit and that communicates with the Roof Control Unit.

I stand to be corrected

 

Excellent. I wonder what caused the problem in the first place (I would heed Thomas' advice and make sure the wiring is ok from the ECU to the seat... e.g. look for shorts to earth with the motor disconnected. Perhaps even check the current the passenger seat motor is pulling in both directions (compared to the driver's seat).

 

Does the roof appear to be trying to move to open or is there no movement at all? This might point to a mechanical problem rather than an electrical problem.

It is possible that there is more than one problem (or that the burnt track was simply a symptom of an underlying problem)

Something which may be worth looking into (but probably wouldn't cause the board damage)...

Thomas mentioned relays on the ECU board, but the system wiring diagram shows two simple external relays. The parts manual on Ricambi also indicates there are two external roof relays (but only seems to show one). These basically reverse the polarity on the roof motor (for closing/opening). One must be relaxed while the other operates. I'm wondering if one is not activating or one is not relaxing properly, causing the other to not control the motor. Unfortunately, they are located in the same area as the ECU (I guess you've put all the console back together?). The part number is #157992. Not too expensive, a common Bosch 5 pin changeover relay (possibly P/N 0332209159, also found on your main relay panels).

Sorry, I've just noticed a relay labelling error in my diagram... I've uploaded a modified version.

Roof Diagram

Of course, there could be many other possibilities... Have you read the forum messages on roof piston position switches?

Cheers
Ian

(EDIT) Sorry, Roger, disregard my external relay solution. I see the bypass switches use the same relays. If both your bypass switches are working, the relays must be fine.