Steve, I guess the first question to ask is whether you've had anything related apart or worked on in the past, such as window switches, door locks, door jamb switches, convenience module (N57), etc?

Also, does the passenger side door lock operate in the same manner, ie, the windows go down when you lock and hold the key in the passenger side?

Looking at the schematics, phew, it's complicated! I'd start by looking at all the door jamb switches, comparing them against the schematics, check the grounds, checking the plug(s) into the convenience module, etc.

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Steve

1992 300CE Sportline Sophie
1990 300E Emma - in the family
1979 240D Josephine - sold, but not forgotten
2004 Pacifica AWD

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