Important Preliminary Checks Before Starting
Perform the
Diagnostic System Check - Engine Controls
before using the symptom tables. Verify that all of the following conditions are true:
• | The engine control module (ECM) and the malfunction indicator lamp (MIL) are operating correctly. |
• | There are no diagnostic trouble codes (DTCs) stored. |
• | The scan tool data is within the normal operating range. |
• | Verify the customer concern and locate the correct symptom listed below. Inspect items indicated under that symptom. |
• | Several of the symptom procedures direct the technician to perform a visual/physical inspection. This important step can lead the technician to the cause of the problem without further checks and can save valuable time. |
• | Verify the correct installation and operation of electronic options, such as lights and cellular phones. |
- Use the following tables when diagnosing a symptom concern:
- If the condition cannot be isolated using the appropriate table, refer to
Intermittent Conditions
for further diagnosis.