Hello. I've got a problem with my '07 xc90 volvo. In the cold season, my car would not warm up my cabin, even if i set that it would blow hot air. Changed water pump, thought the problem was with the pump. After pump service, it started to blow alittle warmer air, but still not the right temperature. Any tips where i should look for problem? Thanks for all the info.

 

not sure I'd start with replacing the water pump but aside from that - does the blower work properly on all speeds? If not check the cabin air filter. does the heat make its way up to the dash but not the floor? Hows the AC - doe that blow cold? Some possible causes - clogged heater core (have you done a coolant flush say in the past 5 years and is the coolant level correct?), debris clogging the evaporator (restricting air from getting to the heater core), faulty blend door (motor or door) - the HVAC has a set of doors that allow the air to flow through the heater core and to the desired vents, faulty thermostat (AC control unit), faulty temp sensor. After testing the blower and air flow, I'd say the next step is to have a fully equipped shop do a scan to check for ECC (electronic climate control) computer faults.

 

I changed water pump just simply because i had to change timing belt, so just to be sure it works, and would not need to do the same job twice. Yeah, blower works fine at all speeds, just the wind it blows is cold/warm. I scanned vehicle, and got CCM-0040 fault code and dont know if its exactly sensors fault for the temperature of air. I checked and sensor was about 200€, and i wouldnt like to invest that sort of money just to make sure that sensor was not the problem.

 

that code points to the ECC's air quality sensor signal - there's some vids on youtube that talk to that. Curious what happens if you toggle the REC switch...