1994 e320 A/C trouble please help!!! - PeachParts Mercedes-Benz Forum

david s poole · #6 07-11-2007, 10:27 AM

it means that this is a control circuit problem.there is a slight poss that the compressor clutch is drawing too much power and has blown the mas relay.you need to find an amp meter and see how many amps being drawn by clutch[should be btwn 5-7] if that is good then we have the speed sensor on the compressor[gk+ and gk-] you can identify these pin sockets [where mas plugs in] and measure with acvoltmeter.notice ac not dc.and then there is the temp sensor in the water jacket that is supposed to cut the comp off during an o/heat and this could have gone bad.not sure of pin designation but will have letter t in it.if measured at mas socket and is a ground then this is problem should be open circuit.try these and see what's going on.