Initial Inspection and Diagnostic Overview

Engine Ignition

Inspection and verification

1. Verify the customer concern.
2. Visually inspect for obvious mechanical or electrical faults.

Mechanical Electrical
^ Fuses
^ Engine oil level ^ Wiring harness
^ Cooling system coolant level ^ Loose or corroded electrical connectors
^ Fuel level ^ Ignition coils
^ Fuel contamination/grade/quality ^ Sensor(s)
^ Exhaust gas recirculation
(EGR) valves ^ Engine control module (ECM)
^ Transmission control module (TCM)

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. Use the approved diagnostic system or a scan tool to retrieve any diagnostic trouble codes (DTCs) before moving onto the symptom chart or DTC index.
^ Make sure that all DTCs are cleared following rectification.

Make sure that all DTCs are cleared following rectification.