PeachParts Mercedes-Benz Forum - View Single Post - 1986 420SEL HVAC

dpetryk · #4 10-21-2001, 08:31 AM

I have similar experiences with the AC. It turned out to be bad solder joints on the printed circuit board inside the climate control unit. MB uses a single sided non-plated thru hole printed circuit boards which suffer from vibration developed micro-cracks. If you are handy you can take the thing apart and re-solder the board.

As for the rough idle, I would check the fuel injectors. They are nortorious for causing that symptom.

Get the dealer to give you the 4 digit security code for the radio and simply key it in when it asks for it. It takes 10 seconds to enable the radio if you have the code.