Sorry I did not go thru your posting completely, but knowing these cars, 2 things are foremost to be repaired:

1.- Upper wiring harness
2.- ETA wiring harness

All other issues are off until those 2 problem areas are addressed

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1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
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