Rear Spoiler Warning Light - Microswitches & motor OK.

[davemac]

Hi everyone,

 

I've had a spoiler warning lamp on since I bought my 1998 996 convertible a few years ago.  As an electronics engineer, I decided I may be able to tackle this issue myself. Before starting, I have read numerous previous posts regarding this issue, and what the fixed-wing bypass harness (996 612 070 51) does.

 

When the rear spoiler is elevated, I'm getting zero Ohms between the Grey/Brown (A2) wire and the Brown (A5) wire, as expected. This becomes open circuit when the lid is lowered. There is then zero Ohms between the Brown (A5) and the Green/Grey (A4) wires, again as expected! The switching of the brake lights works normally too, but still the warning light persists.

 

I am wondering if there could be a corroded plug/socket further forward from the rear of the car because the one at the back is very clean and the microswitch states are normal in both positions. I'm not sure if this is a common fault, but I'm guessing it probably isn't as I can't find anything online. One thing I have noticed is that although the manual up/down wing rocker switch works, I have to keep is pressed down until the wing is down. When I try to elevate the wing manually, the switch triggers the latching function of the relays, but when the spoiler is fully up, I can still hear the motor continuing to turn and the gears slipping inside the rear mechanism. The gears will eventually strip and I'll end up with a bigger problem, so any thought on this nuance would be greatly appreciated.

 

Many thanks,

Dave