The central lock in my right front door won't open if the car has been sitting in the sun for a while.. Heat does strange things to a car.

I am not familiar with the '79 300D. But one of my power windows also only worked when it felt like it.
I replaced the switch in the center console and the problem dissapeared.

On a w124 you can lift the wood off of the center console by pulling up the rear end of the wood piece. Then you can simply pull the window switches out of their sockets.
You can try switching them around to determine if one of them is bad. Very easy.

Freestyler

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Never criticize someone until you've walked a mile in his shoes. That way, when you do, you're a mile away -and you have his shoes!


'86 300E optically converted to '95 E300 (Sold)
-Blauschwarz on silver
-Black leather
-17" AMG & 15" AMG for winter