C Yukon 2WD V8-5.7L VIN R (1999)
Radiator Cooling Fan Motor: Service and Repair
REMOVAL PROCEDURE
The auxiliary cooling fan, if equipped, provides additional cooling under the following conditions:
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Low speed vehicle operations
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Extended idle
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Stop-and-go conditions
In cases of extreme coolant temperatures, the fan runs after engine shutdown. The auxiliary cooling fan is behind the grille on the right side of the
vehicle.
The auxiliary cooling fan circuit consists of the following components:
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The auxiliary fan
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A relay
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The Vehicle Control Module (VCM)
Once the VCM determines that the fan activation is appropriate (a function of coolant temperature, vehicle speed, and A/C system status), the VCM
completes the ground side of the circuit to the relay coil. This energizes the relay, providing 12 volts to the auxiliary fan.
When the VCM determines that the fan operation is no longer required, the relay is de-energized, and voltage is no longer applied to the fan.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. Refer to Battery Cable in Powertrain Management.
2. Remove the radiator grille assembly. Refer to Air Inlet Grille Panel Replacement in Body Front End.
3. Disconnect the connector from the auxiliary fan.
4. Remove the auxiliary fan.
INSTALLATION PROCEDURE
1. Install the auxiliary fan.
2. Connect the connector to the auxiliary fan.
3. Install the radiator grille. Refer to Air Inlet Grille Panel Replacement in Body Front End.
4. Connect the negative battery cable. Refer to Battery Cable in Powertrain Management.
