Upon cold start, the blower works fine on all speeds. After the motor warms up (or approximately 5-10 minutes) the blower will suddenly blow at max speed for about 3 seconds, then it quits completely, remaining unresponsive to any manipulations of the knobs. If I shut the car off for a bit, like to go into a store, when I come out and start the car up the cycle begins again.

Based on research on another site, I've pulled the ACC unit, opened it up and resoldered some known bad joints on the PCB, where the fan speed pot connects. This has made no difference.

There's also plenty written about a transistor on the blower housing which can go bad, but the symptoms are usually either no blower operation at all or 100% max blower. Doesn't quite sound like my issue.

Any thoughts on what I should pursue next? I need to resolve by next weekend when my daughter drives this sled 900 miles back to college.

Thanks for any suggestions!

Doug

current Volvo line up (contrary to what my sig says):
1994 945t
1994 944t
2005 S80 5cyl
2001 S40
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'94 945t; '95 854 base; '05 S80 2.5T