The supercharger intercooler relay is a normally open relay. The relay armature is held in the open position by spring tension. The ignition 1 voltage is supplied directly to the relay coil and to the armature contact when the ignition is ON, or the engine is running. The engine control module (ECM) supplies the ground path to the relay coil control circuit via an internal integrated circuit called an output driver module (ODM). When the engine is running , the ECM commands the relay ON, and the relay coil creates an electromagnetic field. This electromagnetic field overcomes the spring tension and pulls the armature contact into the stationary contact of the relay load circuit. The closing of the relay contacts allow current to flow from the battery to the supercharger intercooler pump. When the ignition switch is turned to the OFF position, power is interrupted to the output driver module in the ECM and the relay electromagnetic field collapses. This allows the spring tension to separate the relay armature contact from the relay load circuit contact, which interrupts current flow to the supercharger intercooler pump.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 43244 Relay Puller Pliers

1. Ignition ON, command the CAC Coolant Pump ON and OFF with a scan tool. Listen for the CAC coolant pump to turn ON and OFF with each command.
2. Verify that the charge air cooler (CAC) coolant level is full. Refer to Charge Air Cooling System Coolant Level Inspection and Charge Air Cooling System Draining and Filling.
3. Ignition ON, command the CAC Clnt. Pump ON and OFF with a scan tool while observing the following control circuit status parameters:

•	CAC Clnt. Pump Relay Ckt. Short Gnd Test Status

•	CAC Clnt. Pump Relay Ckt. Open Test Status

•	CAC Clnt. Pump Relay Ckt. Short Volts Test Status

Each parameter should toggle between OK and Not run or Not Run and OK.

Note: You must perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

1. Ignition OFF, disconnect the INCLR coolant pump relay.
2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 86 and ground.

⇒	If the test lamp illuminates, test the control circuit for a short to voltage.

3. Verify that a test lamp illuminates between the coil circuit terminal 85 and ground.

⇒	If the test lamp does not illuminate, test the B+ coil circuit for an open/high resistance. If the circuit tests normal and the B+ circuit fuse is normal, test or replace the intercooler pump relay.

4. Verify that a test lamp illuminates between the B+ switch circuit terminal 30 and ground.

⇒

If the test lamp does not illuminate, test the B+ switch circuit for an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the voltage output control circuit terminal 87 for a short to ground. If the circuit tests normal, test or replace the intercooler water pump.

5. Disconnect the harness connector at the intercooler water pump.
6. Test for less than 2 Ω between the intercooler water pump ground circuit terminal A and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

7. Connect the harness connector at the intercooler water pump.
8. Connect a 30A fused jumper wire between the B+ switch circuit terminal 30 and the voltage output control circuit terminal 87. Verify that intercooler water pump is activated.

⇒	If the intercooler water pump does not activate, test the voltage output control circuit for an open/high resistance. If the circuit tests normal, test or replace the intercooler water pump.

9. Verify that a test lamp does not illuminate between the B+ coil circuit terminal 85 and the control circuit terminal 86.

⇒	If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.

10. Remove the test lamp.
11. Command the CAC Clnt. Pump ON with a scan tool. Verify the scan tool CAC Clnt. Pump Relay Ckt. Short Volts Test Status parameter is OK.

⇒	If not the specified value, test the control circuit for a short to voltage. If the circuit tests normal, replace the ECM.

12. Install a 3A fused jumper wire between the control circuit terminal 86 and the B+ circuit terminal 85. Command the CAC Clnt. Pump ON with a scan tool. Verify the scan tool CAC Clnt. Pump Relay Ckt. Short Volts Test Status is Fault.

⇒	If not the specified value, test the control circuit for an open/high resistance. If the circuit test normal, replace the ECM.

13. If all circuits test normal, replace the INCLR intercooler pump relay.

Coolant Pump Relay

1. Ignition OFF, disconnect the INCLR coolant pump relay.
2. Test for 135-175 Ω between terminals 85 and 86.

⇒	If the resistance is not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

•

30 and 86

•

30 and 87

•

30 and 85

•

85 and 87

⇒	If not the specified value, replace the relay.

4. Install a 10A fused jumper wire between relay coil terminal 85 and 12V. Install a jumper wire between relay coil terminal 86 and ground. Test for less than 1.0Ω between switch terminals 30 and 87.

⇒	If greater than the specified range, replace the relay.

CAC Pump Dynamic Test

1. Install a 30A fused jumper wire between the B+ terminal B and 12V.
2. Install a jumper wire between the ground terminal A and ground.
3. Observe for the CAC pump to activate.

⇒	If the CAC pump does not activate, replace the CAC coolant pump.

Perform the Diagnostic Repair Verification after completing the repair.