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Starter Generator Control Module Cooling Fan Inoperative

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Starter Generator Control Module Cooling Fan Inoperative

Step Action Yes No
Schematic Reference: Engine Cooling Schematics 
Connector End View Reference: Cooling System Connector End Views 
DEFINITION: The starter generator control module (SGCM) coolant fan motor does not operate.
1 Did you perform the Diagnostic System Check - Engine Cooling? Go to Step 2  Go to Diagnostic System Check - Engine Cooling 
2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the SGCM coolant fan ON and OFF.
Does the SGCM coolant fan turn ON and OFF with each command?
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3
  1. Turn OFF the ignition.
  2. Remove the SGCM coolant fan relay.
  3. Probe the battery positive voltage circuit of the SGCM coolant fan relay switch side with a test lamp that is connected to a good ground.
Does the test lamp illuminate?
Go to Step 4  Go to Step 7 
4 Connect a 20 A fused jumper wire between the battery positive voltage circuit and the SGCM coolant fan motor supply voltage circuit at the coolant fan relay.
Does the coolant fan operate?
Go to Step 10  Go to Step 5 
5
  1. Disconnect the SGCM coolant fan motor connector.
  2. Probe the SGCM coolant fan motor supply voltage circuit at the harness connector with a test lamp that is connected to a good ground.
Does the test lamp illuminate?
Go to Step 6  Go to Step 8 
6 Probe the harness connector of the SGCM coolant fan motor with a test lamp connected between the SGCM coolant fan motor supply voltage circuit and the ground circuit of the coolant fan motor.
Does the test lamp illuminate?
Go to Step 11  Go to Step 9 
7 Repair the battery positive circuit of the SGCM coolant fan relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 14  -
8 Repair the supply voltage circuit of the SGCM coolant fan motor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 14  -
9 Repair the ground circuit of the SGCM coolant fan motor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 14  -
10 Inspect for poor connections at the SGCM coolant fan relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 14  Go to Step 12 
11 Inspect for poor connections at the harness connector of the SGCM coolant fan motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 14  Go to Step 13 
12 Replace the SGCM coolant fan relay.
Did you complete the repair?
Go to Step 14  -
13 Replace the SGCM coolant fan motor. Refer to Cooling Fan - Starter/Generator Control Module Replacement .
Did you complete the repair?
Go to Step 14  -
14 Operate the system in order to verify the repair.
Did you correct the condition?
System OK Go to Step 2