Important Preliminary Inspections Before Starting
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
Perform Diagnostic System Check - Engine Controls before using the symptom tables, and verify that all of the following are true:
- The powertrain control module (PCM) and malfunction indicator lamp (MIL) are operating correctly.
- There are no DTCs stored.
- The scan tool data is within the normal operating range, refer to Scan Tool Data List .
- Verify the customer concern and locate the correct symptom in the table of contents. Inspect the items indicated under that symptom.