Looking for some guidance with a window issue. I have an `82 300SD. Car is fairly new to me – previous owner disclosed that the passenger side window wasn't working – I've owned several other 126's and replaced a number of window switches in the past – figured that was all that it was (this car has a single switch module for each side, feed, or ground (?), is the frontmost pin). About three days after I got the car the drivers side window failed, both rear windows worked as they should; at that point the car went into storage for about six months and I just recently retrieved it. I opened the center console, removed the switches and determined that I have 12 volts between the frontmost plug socket and socket #3 on both the front and rear plugs (again, the rear windows work fine). The previous owner told me that they had replaced the window regulator on the passenger side just prior to the sale.

I admit that I'm perplexed at this point – both switches are n ew, there is no noise coming from the doors (I find it hard to believe that both front motors failed at the same time) – ANY IDEAS??

 

well do you have power at motors?

 

Yes, but only 9.2 V

 

The wires were disconnected from motor when you measured voltage?

You just connected to wire harness connector for motor?
What was battery voltage at this time?

If you were connected to motor well then disconnect.

I would then test motor with direct connection to a fully charge 12VDC battery and see if she spins or not.

 

To add, use the frame of the car as the ground for your voltage reading.