Possible malfunctions of the heating system, their causes and remedies

Fan not working

Blown fan motor fuse

Check fuse, replace if necessary.

Faulty fan switch

Remove the switch and check it, and if necessary replace it with a new one.

Faulty resistor

Remove the resistor and check that there is voltage to the motor. If there is no voltage or it is low, then replace the resistor with a new one.

Faulty fan motor

Remove motor and resistor. Check if voltage is being supplied to the motor. If voltage is supplied, replace the motor with a new one.

Fan speed is not adjustable

Faulty resistor

Replace resistor.

Low blowing air temperature

Low coolant level

Check the coolant level in the expansion tank. Top up if necessary.

Clogged cabin filter

Clean the filter.

Heater radiator leaking or clogged

Replace radiator. The work is done in the workshop.

Noises in the fan

Dirt, leaves

Remove and clean the fan, clean the air duct.

Fan impeller imbalance, defective bearing

Remove the fan and check for ease of movement.

Sickening smell in the cabin. Windows fog up when heater is turned on

Heater radiator leak

Check the tightness of the pressurized radiator in a workshop. If there is a coolant leak from the heater core, replace it.