hot/cold on left side--opposite on right--300sd--140 body

[jack]

everything fine with climate control, then-- BAM-- right side vents start blasting HOT air. very inconsistent on time, maybe immediately, maybe 2 minutes, maybe longer. Then left side tries to compensate and blower goes on high. This happens both in Economy or AC mode. it happens at all/any exterior temperatures

1993 300SD 140 body

[kropsch]

Hi Jack:
In my 500 SEC as in the C 280, when the outside temperature is not hot, and the thermostat is not adjusted for a low temperature, sometimes the middle vent blows cold air and the side vents blow hot air. This is normal. If the thermostat temperature is decreased the three vents blow cold. I don't agree, but Mercedes say that this is better than simply turn off the compressor.

[john m]

Hello Everyone
The symptoms sound far to strange too be normal.
I whish you where close enough to bring your cars in to the shop.
I recently aided a friend with a similar problem on her MB, turned out to be bad alternator and climate control head.

[Peter Guenther]

Just a stab in the dark, since the car has individual temp controls, have you tried moving them (maybe intermittent)

[joeym7]

Hi One of your aux water pumps may be out little tough to get at also try to recalibrate your acc push button control module.joeym