Mercedes S-class W202

1993-2000 of release

Repair and car operation

6.6. Diagnostics of malfunctions of system of heating

THE GENERAL DATA

THE REASON	ELIMINATION METHOD
The heating fan does not rotate
Has fused a safety lock of the electric motor of the fan.	Check up a fan safety lock, in case of need – replace.
The fan switch is faulty.	Check up, whether pressure on the fan electric motor moves. If is not present, remove and check up the switch.
The electric motor is faulty.	Replace the fan electric motor.
The heating fan does not rotate on one of steps of speed
Defective additional resistance	Replace additional resistance.
Too low power of heating
Too low level of a cooling liquid	Check up level of a cooling liquid, in case of need – add cooling liquid.
The heating valve does not open	Check up the electromagnetic valve in system of access of water, make passed.
Негерметичен or the heat exchanger is littered	Replace the heat exchanger (work for repair shop).
Nagretyj air has a sweetish smell, at heating inclusion glasses mist over
Негерметичность the heat exchanger	Check up cooling system on tightness. Replace the heat exchanger (work for repair shop).
Noise at work of the fan of heating
Fan pollution	Remove the fan, clean the air channel.
Disbalance крыльчатки the fan, malfunction of the bearing	Remove the electric motor of the fan and check up ease of its rotation.