The a/c fan on my 2002 Volvo v40 will suddenly speed up for a few seconds, and then go back to the original speed. It happens if the a/c is on or off. All speeds work otherwise.
Any ideas?
Tom
AC fan . . . I’m assuming you mean the blower motor, which is located near the glove box.
If you mean the blower motor, you might have a bad blower resistor pack.
I agree with the above unless it happens with the fan on in the highest position. If it happens in the highest position, you may have a major problem brewing, like a bad voltage regulator that could damage the sensitive electronics in the vehicle.