Mercedes Benz repair: Failure to start, number search results, mercedes benz 300se

Question
1989 benz 300SE 160,000 plus miles. austin texas

w/ turning the key in the ignition you hear the (key    in) buzzer and the fan will come on but you can not control sun roof, windows, or turn the engine over. (yes the battery is charged)(all fuses are ok)
Help the everything is stuck open and it't been raining, not to mention it can't be driven.

Answer
Best guess:
Bad battery ground/connection or ignition switch failure, three screws hold the switch in place.
You can access it from under the console.

PART NUMBER SEARCH RESULTS WITH PRICES
Vehicle 1989 Mercedes Benz 300SE
Part: Ignition Switch
 Note:  Electrical Portion
M5050-32967 Ignition Switch IN STOCK $27.93  
  
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