the blower motor seems to have a mind of it own. speeding up and slowing down randomly in the munal mode as well as the automatic mode.I unplugged the blower motor resistor and plugged it back in and the blower wouldnt work at all anymore.I change the blower resister with a new one from volvo. having the same problem. any suggestions. Thanks
blower fan acting eratic on 2002 Volvo S40
by volvo s40 in Fair Lawn, NJ on December 07, 2010
ANSWER by dandd on December 07, 2010
I would check your blower motor ground circuit, it may be loose or corroded and I have seen that cause random blower speeds.