Originally Posted by
g3air
Earlier this year I ran the test above a couple of times with mixed results (sometimes all good, sometimes not). I went ahead and did the repair on the duovalve and thought all was well. However, the problem (unpredictable occurrences of hot air blowing on the driver's side according to Cathy) has come back for quite a time. I just ran the above test again this AM and, of course, everything worked perfectly. My wife is the primary on this wonderful car (bought new in 2005) and she loves it, but we would truly like to have it working consistently well. I am getting a bit ancient now (closing on 80) and can't easily do the maintenance I have been able to do in years before (top hydraulics, top replacement, accelerator pedal, etc.). I will never take the Crossfire to the dealer, but we do have a reliable independent (somewhat pricey) repair shop nearby here in SW florida. There is no Mercedes dealer nearby. Any advice for how we might ensure the magnificent vehicle AC fixed once and for all would be most appreciated. Thanks in advance!
If ONE side goes warm and the OTHER side stays cold, it is either the duovalve or the climate control module. (I do not think a failed temp sensor on the driver's side heater core/evaporator would cause this, let me think about that but again I don't see how, I keep going back to the climate module or duovalve.)
I will say, there are more and more complaints of failed climate control modules on our Facebook pages - our cars are aging and new failure modes are coming to our attention. I'd consider finding a climate control module from a "parts car" and giving that a try.
Attached below is PDF of how to remove/reinstall a climate control module.