Engine Cooling: Overview Lincoln Aviator I

Scheme 3

Normal Operation

Under normal operation, the power distribution box (PDB) supplies power to the cooling fan relay on circuit 1153 (RD/BK) through the No. 8 fuse. The PCM supplies ground on circuit 1154 (WH/BK) to engage the cooling fan relay when any of the following conditions are met

1. The engine temperature is above 99°C (210°F).
2. The transmission oil temperature is above 110°C (230°F).
3. The A/C compressor is commanded on.

Power is then supplied on circuit 1155 (YE/BK) to turn the fan on. Ground for the cooling fan motor is supplied through circuit 1205 (BK) to chassis ground.

Under normal operation, the power distribution box (PDB) supplies power to the cooling fan relay on circuit 1153 (RD/BK) through the No. 8 fuse. The PCM supplies ground on circuit 1154 (WH/BK) to engage the cooling fan relay when any of the following conditions are met

1. The engine temperature is above 99°C (210°F).
2. The transmission oil temperature is above 110°C (230°F).
3. The A/C is commanded on.

Power is then supplied on circuit 1155 (YE/BK) to turn the fan on. Ground for the cooling fan motor is supplied through circuit 1205 (BK) to chassis ground.