Circuit/System Testing

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Observe the DTCs with the scan tool.
- If DTC P0602 or P062F is set, attempt to program the ECM before replacing the ECM. Refer to Service Programming System (SPS) .
- If DTC P0606 was set while performing SPS Programming, clear the DTCs and exit the diagnostic.
- If DTC P0606 was set with DTC P0851 or P0852, first go to Diagnostic Trouble Code (DTC) List - Vehicle .
Test the voltage and ground circuits to the control module for the following:
- A short
- An open
- High resistance

IMPORTANT: DTC P2610 can be set with a loss of battery voltage to the ECM with the ignition ON. The ignition must be in the OFF position before disconnecting the ECM.

If DTC P2610 is set, turn the ignition OFF and then completely disconnect the ECM harness connector from the ECM for approximately 1 minute. Reinstall all of the ECM connectors and then attempt to clear codes with the scan tool.
- If DTC P2610 resets after code clear, replace the ECM.
Replace the ECM.