Starter Generator Control Module Coolant Pump Inoperative. GMC Truck GMC C Sierra

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2005 🢒 GMC C Sierra - 2WD 🢒 Engine 🢒 Engine Cooling 🢒 Starter Generator Control Module Coolant Pump 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 pump does not operate under certain conditions.
1	Did you perform the Diagnostic System Check - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2	SGCM and red box are the same part. Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the SGCM pump speed ON in powertrain special functions, SGCM output controls. Does the SGCM coolant pump operate?	Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems	Go to Step 3
3	Disconnect the red box cool pump relay. Connect a test lamp between the control circuit and the coil supply voltage circuit of the red box cool pump relay. With a scan tool command the SGCM pump speed ON and OFF. Does the test lamp illuminate?	Go to Step 4	Go to Step 5
4	Connect a 10-amp fused jumper wire between the battery positive voltage circuit and the coolant pump supply voltage circuit of the after-boil relay. Does the after-boil coolant pump operate?	Go to Step 12	Go to Step 8
5	Test the control circuit of the red box cool pump relay for an open or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 6
6	Test the battery positive voltage circuit of the red box cool pump relay for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 7
7	Test the voltage supply circuit of the red box coolant pump for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 10
8	Test the voltage supply circuit of the red box coolant pump for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 9
9	Test the ground circuit of the red box coolant pump for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 11
10	Replace the SGCM (red box). Refer to Generator Control Module Replacement in Engine Electrical. Did you complete the replacement?	Go to Step 13	--
11	Replace the generator control module coolant pump. Refer to Generator Control Module Coolant Pump Replacement . Did you complete the replacement?	Go to Step 13	--
12	Replace the red box relay. Did you complete the replacement?	Go to Step 13	--
13	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2