Cooling system check - Troubleshooting

In the event of faults in the cooling system, for example insufficient heating output, engine not reaching operating temperature, or overheating, it is possible to track down the fault cause using simple means. First of all, the cooling system should be checked for a sufficient coolant level , contaminants, antifreeze, and leaks. The V-belt or V-ribbed belt should also have sufficient tension.

Depending on the symptoms, troubleshooting can then be continued by monitoring components or recording temperatures as follows:

Is the displayed temperature realistic?

• If necessary, check the coolant temperature sensor and indicating instrument ✓

Are the radiators or upstream components (condenser) free from contaminants to ensure an unrestricted air flow rate?

• If necessary, clean the components ✓

Does the radiator fan or auxiliary fan work?

• Check the switch-on point, fuse, thermal switch, fan control unit; check for mechanical damage ✓

Does the thermostat open?

• Record the temperature before and after the thermostat, remove the thermostat and inspect in a water bath if necessary ✓

Is the radiator clogged?

• Check the temperature at the input and output of the radiator, check the flow rate ✓

Is the coolant pump working?

• Check whether the pump wheel sits firmly on the drive shaft ✓

Are the overpressure and/or underpressure valves of the radiator cover and/or expansion tank working?

• If necessary, use the test pump and check whether the seal of the cover is present and/or damaged ✓

Is the displayed temperature realistic?

• If necessary, check the coolant temperature sensor and indicating instrument ✓

Is the thermostat constantly open?

• Record the temperature before and after the thermostat, remove the thermostat and inspect in a water bath if necessary ✓

Does the radiator fan or auxiliary fan work permanently?

• Check the switch-on point, thermal switch, fan control unit ✓