Circuit/System Verification
- Ignition OFF, inspect the cooling system surge tank for the proper coolant level. Refer to Cooling System Leak Testing and Draining and Filling Cooling System (LY7, LZ4, LZ9 Static Fill) .
- Ignition OFF for 8 hours or more.
- Ignition ON, observe the scan tool IAT and ECT sensor parameters. The ECT, IAT, and ambient temperature should be within 15°C (27°F) of each other.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.