Air conditioning works but no fan inside same with heater
1990 Mercedes-Benz 300CE

Air conditioning works but no fan inside same with heater

(1990 Mercedes-Benz 300CE)
when heater and air conditioning comes on no fan, sometimes in long trips fans come on but for short times ?
2 answers & 2 comments
Popular Answer
There are three things here to look at the blower motor resistor which is just behind the battery, and the auxiliary fuse holder that supplies power to the motor (25 amp fuse), blower motor is in the engine compartment in the center top (under the cowl panel under the wiper motor).
Fuse 11 (an 8 amp fuse ) also provides power to the heater controls/ motor circuit but if it fails the horn also fails.
Red wire at the fan motor should make the blower motor operate when power is supplied to it if the blower motor is good, the brown wire at the motor is ground.
Usually the blower motor resistor that fails.
Sign in to reply
General Diagnosis
$88 - $111 Learn More
There are three things here to look at the blower motor resistor which is just behind the battery, and the auxiliary fuse holder that supplies power to the motor (25 amp fuse), blower motor is in the engine compartment in the center top (under the cowl panel under the wiper motor).
Fuse 11 (an 8 amp fuse ) also provides power to the heater controls/ motor circuit but if it fails the horn also fails.
Red wire at the fan motor should make the blower motor operate when power is supplied to it if the blower motor is good, the brown wire at the motor is ground.
Usually the blower motor resistor that fails.
Sign in to reply
on March 12, 2010
Try the blower switch contacts. Remove the switch and clean the 4 relay type contacts. The contacts gets become dirty over the years.
Sign in to reply

Similar Questions

View answers to similar questions from RepairPal's community of auto experts and enthusiasts.
Its cold ,then goes cool to warm you can turn off for a few minutes and turn it back on and cold for about 5 miles i...
Hi folks, i have a maxima and there's water running into the floorboard when it rains. i removed the plastic cover...