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Asked by: Blandine Pfafflin
home and garden indoor environmental qualityWhat does the cooling fan module do?
Also asked, how does a fan control module work?
The engine control module has two relay-ground terminals—one for the low speed and the other for the series-parallel relay. So voltage flows through the left side cooling fan motor, through one circuit provided by the series-parallel relay contacts, through the right side cooling fan motor to ground.
In this manner, when should the cooling fan come on?
To check the temperature at which the fan comes on, turn the A/C off and keep the engine running until it reaches normal operating temperature. Most fans should come on when the coolant reaches about 200 to 230 degrees. If the fan does not come on, something in the control circuit is defective.
Symptoms of a Bad or Failing Cooling Fan Relay
- Engine running hot. One of the first symptoms commonly associated with a bad or failing cooling fan relay is an engine that runs hot or overheats.
- Cooling fans do not function. Non-functional cooling fans are another common symptom of a potential problem with the cooling fan relay.
- Cooling fans stay on at all times.