A/C & heater problems on 400 SE
 

A/C works, compressor very noisy after running over 1/2 hour (ordering a new one), but can not turn it off. Heater does not work at all. No MB mechanics on the Island, Kauai, HI. Could use some help. Thanks, Steve

The compressor should shut off when depressinf the EC OR "0" buttons. IF not someone has wired the compressor to run all of the time.
Heat is controlled by the heater valve assembly(duo-valve) about a foot behind the left headlight, under a black plastic cover.

re: 400 SE A/C & heater
 

Usually I get no responce when I push my "0" or EC button. Today it turned off when "0" button was pushed. Can read sensor values but get the same sensor readings when I try to read the DTC's. Used the values from K6JRF (Great Site!) so not sure if the procedure is the same on my'92. Guess I should put a new kit in my duo valve for the heating problem. Thank you for the help. Need that heater! It gets down to 65 degrees during the winter!