I'm having problems with the Climate Control Blower Motor Speed.

The hot and the cold side of things seems to work ok, and but the actual speed of the blower keeps fluctuating. Very annoying as when the blower should be slow it kicking out at high speed. Either your burning up or freezing. Manual fan settings only work once in a while.

I just purchased the car so I have no idea if it did this at an earlier date.

I'm thinking it may be the Pushbutton control unit but would like to find out what others think before I fork over the cash for one.

I ran a diagnostic on it and I'm getting the following codes:
B1232 Refrigerant Pressure Sensor (B12)
B1416 Heating Water Circulation Pump (A31M)
B1417 Duo Valve (Y21)
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My question is, could the pressure sensor be causing the other problems or are they unrelated ? I believe they all tie together somehow, but not sure exactly how. Any help is greatly appreciated.

Thanks

The codes that you got will affect the temp but not the blower. That car as well as all MB's from around 1986 (except 190's) have electronic blower controls. The electronic blower regulator is a common problem. MOUNTED to the blower motor under the passenger under-dash panel. ALSO the micro-filter needs replacement every 20K-30K miles.

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Hi M.B Doc, Thanks for the quick reply.

Since I am getting these codes, is there a more common problem with one of the three that could cause the others ?

ie.. Could the Duo Valve cause the others to trigger ? or I guess the question is, which sensor/part should I replace first (or in what order) to at least get rid of the codes?

Thanks

The fix for the blower RPM speed randomly changing appears to be the blower motor regulator.
Which, here in California can now be purchased seperately.

~approx $110

seems to be working ok now!