Cooling Fan System On-Vehicle Inspection

Engine Hybrid System. Corolla. Zre142 Aze141
2Az-Fe Cooling. Corolla. Zre142 Aze141

  1. INSPECT COOLING FAN OPERATION AT LOW TEMPERATURES (Below 94°C (201°F))

  2. INSPECT COOLING FAN OPERATION AT HIGH TEMPERATURES (Above 96°C (205°F))

Cooling Fan System -- On-Vehicle Inspection


HINT:
It is normal for the cooling fans to sometimes operate when the ignition switch is turned from ACC to ON.


1. INSPECT COOLING FAN OPERATION AT LOW TEMPERATURES (Below 94°C (201°F))

  1. Turn the ignition switch to ON with the A/C switch off.

  1. Check that the cooling fans stop.
    If either does not, check the cooling fan relays and engine coolant temperature sensor, and then check for disconnection of the connector or a wire break between the cooling fan relay and engine coolant temperature sensor.

  1. Disconnect the engine coolant temperature sensor connector.

  1. Check that the cooling fans operate.
    If either does not, check the fuses, cooling fan relays, ECM and cooling fan, and then check for an open circuit in the cooling fan relay.

  1. Reconnect the engine coolant temperature sensor connector.



2. INSPECT COOLING FAN OPERATION AT HIGH TEMPERATURES (Above 96°C (205°F))

  1. Start the engine, and then raise the coolant temperature above 96°C (205°F).

    HINT:
    Coolant temperature is the value detected by the engine coolant temperature sensor on the cylinder head.

  1. Check that the A/C switch is off.

  1. Check that the cooling fans operate.
    If either does not, check the fuses, engine coolant temperature sensor, cooling fan, harness or connector.