The blower/fan inside the car doesn't turn off. I was sitting in car with engine running. Turned car off and the blower continued to run. Turned car off again, this time removing key and opening door. Problem continued. Albeit it was late in day I was able to speak with service at dealer who stated he never heard of this kind of problem and as they were closing suggested I remove cables to the battery as a means of tripping the computer. Found mechanic who removed and reattached the cables with no luck. Mechanic then checked fuses..not the issue. Checked for codes - no issue there. Finally mechanic suggested a guess that the issue is a transmitor. There after upon driving home (total of ten miles) I turned the car off two times, for about two minutes with blower continuing to run. When I arrived home and turned car off, the low battery light came on ( purchased battery about 1 year ago from Volvo dealer). Note while driving home I noticed what appeard to be the blower moving from the floor to the body to the defrost positions without any direction from me. PS although the display sceen reflected the blower as being off, blower was blowing heat as if it was selected to the highest speed; control for amount of heat being blown not working. Any suggestions on what this issue could be would be very much appreciated. And should the brief moments I left car off have drained the battery as it did?

 

Sounds like a ghost in the machine!

Last May, the alternator in my 2002 S60 died as I was driving on the highway. I got a message about overcharging, and was told to pull off the road safely. I did. I turned the car off. I restarted it, and drove it about 1/8 of a mile. During that drive, the blower motor was on full blast, the windows wouldn't roll down, and the ABS kept grabbing preventing me from going over 15 MPH. Needless to say, I needed a new alternator and a new battery.

Could be related?

 

when the alternator goes on a modern car, the system voltage will eventually go below that required by the various computers (including the climate control) - which can lead to all sorts of unpredictable behavior. You can put a volt meter across the battery and see if the voltage is about 12.6V with the engine off (anything lower means a bad battery) and about 14+- with the engine running. If its over 16 or so, you are overcharging the system (bad voltage regulator) if it remains around 12, the system is not charging at all.

The thing about these cars is they also have a limp mode which allows you to drive slowly for a short period of time (say to get off an exit) but with reduced power to minimize further damage. Fix the root cause and the car will exit limp mode.