Circuit/System Verification

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

Verify that DTCs P2600, P2602 and P2603 are not set.
- If any auxiliary coolant pump DTCs are set, repair the DTC first. Refer to DTC P0480, P0481, P0691, P0692, P0693, or P0694 .
Ignition ON, command the auxiliary coolant pump relay ON and OFF with a scan tool. Verify that the pump turns ON and OFF when changing between the commanded states.
- If the auxiliary coolant pump does not activate, refer to After Boil Coolant Pump Inoperative .