Diagnostics of heating system faults
Cause | Method of elimination |
The heating fan does not rotate | |
| The fan motor fuse has blown. | Check the fan fuse and replace if necessary. |
| The fan switch is faulty. | Check if there is voltage to the fan motor. If not, remove and check the switch. |
| The electric motor is faulty. | Replace the fan motor. |
The heating fan does not rotate at one of the speed levels | |
| Defective additional resistance | Replace the additional resistance. |
Heating power is too low | |
| Coolant level too low | Check the coolant level and top up with coolant if necessary. |
| The heating valve does not open | Check the solenoid valve in the water access system, make it passable. |
| The heat exchanger is leaky or clogged | Replace the heat exchanger (work for a repair shop). |
The heated air has a sweetish smell, and when the heating is turned on, the windows fog up | |
| Heat exchanger leakage | Check the cooling system for leaks. Replace the heat exchanger (work for a repair shop). |
Noise when the heating fan is running | |
| Fan contamination | Remove the fan and clean the air duct. |
| Fan impeller imbalance, bearing failure | Remove the fan motor and check that it rotates easily. |