cooling fan/a/c issue

martin9586 · Post by **martin9586** » 13 Feb 2011, 10:23

2003 S40.

For a while now I have been having an issue with the electric cooling fan and the a/c. The cooling fan turns on and off constantly, as in , starting the car the fan will turn off run for a while then turn off then turn back on again. The periods of time between when it turns on and off are completely random. As I said a lot of the time it will turn on as soon as the car is started. This will happen all the time the car is running.

I did have a "check engine" light come on the other day. I took it to my mechanic, he scanned the code and it said that the coolant wasn't getting hot enough fast enough. I replaced the thermostat but the fan still comes on whenever it feels like it.

The other issue is that the a/c will turn on and off whenever it feels like it too. I'll be driving along with the a/c / heater turned off and all of a sudden the a/c button light will turn green and the blower starts blowing cold air into the cabin.

It dosn't matter how hot or cold it is outside these problem keep occuring. I am completely confused. How can the a/c turn on by itself when you have the blower dial turned to 0?

Any sugguestions would be appreciated.

Post by **billofdurham** » 13 Feb 2011, 11:58

Welcome to Matthew's Volvo Site.

The cooling fan is linked to the AC coming on when the AC is running. The second part of your problem would appear to be the resistor pack on the heater starting to fail. It is a common fault on the S/V40.

Look at this thread for more detail and how to repair it.

Bill.