Symptoms Verification: Notes

WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Before using the Symptom tables, perform the following inspections:

Ensure that the engine control module (ECM) and malfunction indicator lamp (MIL) are operating correctly.
Ensure that there are no DTCs that are stored.
Ensure that the scan tool data is within a normal operating range.
Verify the customer concern.
Perform the Visual/Physical Inspection in this section. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.