Is your Volvo’s climate control clicking from the dash when you adjust the cabin temperature? If so, it could be the blend motor. Blend motor = ECC motor = the thing that blends hot and cold air to give you that perfect 70 degrees from the vents.
If Your Climate Clicks…
The clicking means it’s at the end of its travel, and you need to take it out and use a 9v battery to move the arm to one side. Longtime MVS member JBRollo took his out and reset the travel and eliminated the clicking:
Had a clicking A/C Blend motor, mainly around the 72 degree setting. One problem with installing a replacement has always been the calibration. But that requires taking it to the dealer ($$$!). I found that you could match the shaft position of the old Actuator with the new one by simply using a 9 volt battery. Caution: the pin selection is critical as only two pins control the motor. The other pins go to the Climate Control Computer…stay away from them!
The travel on my blend motor (P/N 9142629), the passenger side, was only about 180 degrees and moved very slowly with 9 volts. Its a simple matter to match the position of the old with the new. Use the hookup pictured below (the two pins just above the blank space are the correct ones). Reverse the current to reverse the motor.
My car is a 2000 S70 SE but the connector/pin pattern on many other model years and models seem to be the same.
Worked great for me. No codes. No further calibration needed. But remember: I got to mine before a total failure. At the least, this is a good procedure to align the actuator shaft for installation.