I recently purchased a 1982 300sd. All the power windows didnt work when I bought it and prev owner never bothered fixing them. I tried replacing every fuse in the car and then replacing center console swiches (note the originals were covered in coffee or coke syrup) and the led lights on the new switches dont even come on leading me to believe they arent receiving any power. anybody else have any cheap solutions to try? also note the driver side power seat adj. doesnt work and niether does tachometer.

 

the problem is easy to follow by using a 12 volt test light.

i guess your problem is on the F1 (diode V1 or relay K6).

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