Circuit/System Testing
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.
IMPORTANT:
Diagnose and repair any communication DTCs prior to performing this testing.
Program the engine control module (ECM) with the latest software version and recheck for DTCs.
- If the DTC resets after programming or if the ECM already contains the latest software version, replace the ECM.