Why does the Jetta's fan turn on when the water temperature reaches 102 degrees?
1 Answers
Jetta's fan turning on at 102 degrees water temperature may be related to the fan, temperature control switch, or thermostat. Turning on with AC: If the fan turns on when the AC is activated, this can rule out faults with the fan (including the fan motor). Check the temperature control switch: (Also known as the thermal switch, located near the fan). Directly connect the live wire to the 1st gear wire and the live wire to the 2nd gear wire. If the fan turns on in both cases, proceed to the next step. If either gear fails to turn on, the temperature control switch is faulty. However, this does not rule out other faults, but the priority is to replace the temperature control switch. Check the thermostat: If the temperature control switch is not faulty, check the thermostat. A faulty thermostat can cause the water temperature to rise, triggering the fan to turn on.