PeachParts Mercedes-Benz Forum - View Single Post

JimF · #3 02-21-2008, 12:29 PM

Those are an expanded set of "operational" codes for all W140 cars as of 9/95 and on.

Peter's link takes you to my pages, Menu#15 that gives both operational and diagnostic codes up to 8/95.

As you can see MB expanded the readout include some additional operational parameters that could help in diagnosing A/C problems.

In both systems, the two 'key' readings come from #5, "Evaporator Temp Sensor" and #7, "Refrigerant Pressure", in bar. (1 bar = 14.7 psi).

You can drive along and see the 'health' of your A/C system. #5 should cycle between 37 (or lower) to 43 on a hot day. #7 should cycle between 7 to 16 bar on a hot day. If it does, your A/C is working fine!