Preliminary Checks

Before proceeding with Symptom Diagnosis, perform the "On-Board Diagnostic (OBD) System Check" and verify all of the following items: Component Tests and General Diagnostics

- The powertrain control module (PCM) and malfunction indicator lamp (MIL) (Check Engine lamp) are operating correctly.
- There are no DTC(s) stored.
- Tech 2 data is within normal operating range. Refer to Typical Scan Data Values.
- Verify the customer complaint and locate the correct symptom in the table of contents. Perform the procedure included in the symptom chart.