Circuit/System Testing (Set in ECM)
WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, open the hood to disable the Auto-Stop function. Refer to Hybrid Modes of Operation Description .
- Ignition ON, verify the scan tool hood position parameter displays Open.
- If the hood position does not display Open, refer to Diagnostic Trouble Code (DTC) List - Vehicle for DTC P254F.
- Observe the DTCs with the scan tool.
- If DTC P0602 is set, attempt to program the ECM before replacing the ECM. Refer to Service Programming System (SPS) .
- If DTC P0602 resets, replace the ECM.
- If DTC P16F3 is set with other non-internal ECM DTCs, diagnose the non-internal ECM DTCs first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Test the voltage and ground circuits to the ECM for the following:
- A short
- An open
- High resistance
IMPORTANT:
An intermittent or momentary, less than 1 second, loss of system voltage during throttle tip-in may set DTC P060D.
- If all circuits test normal, replace the ECM.