For 1990-2009 cars

Scan Tool Output Control | Additional Menu Selection(s) | Description
--- | --- | ---
Fans Low Speed | Special functions/Engine Output Control/Fan Relays | This function operates the engine cooling fan at low speed by enabling the fan low speed relay. The normal commanded state of the relay is None. When commanded ON/OFF, both cooling fans turn ON/OFF. The system remains in the commanded state until cancelled by the scan tool. The ECM allows relay control when the following conditions are met:

• | The ignition is ON, with the engine OFF.

• | The engine is running.

• | The transmission must be in Park or Neutral.

• | The A/C request is OFF.

• | The engine coolant temperature is less than a predetermined value.

Fans High Speed | Special functions/Engine Output Control/Fan Relays | This function operates the engine cooling fan at high speed by enabling the fan high speed relay. The normal commanded state of the relay is None. When commanded ON/OFF, the cooling fan turns ON/OFF. The system remains in the commanded state until cancelled by the scan tool. The ECM allows relay control when the following conditions are met:

• | The ignition is ON, with the engine OFF.

• | The engine is running.

• | The transmission must be in Park or Neutral.

• | The A/C request is OFF.

• | The engine coolant temperature is less than a predetermined value.