Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Procedure Overview
When running any tests using New Generation Star (NGS) scan tester, ignition switch must be in RUN position, transmission must be in Park, driver's seat not occupied, parking brake applied, all doors and trunk lid closed, and all accessories switched off. Follow these steps to ensure successful diagnosis using vehicle On-Demand self-diagnostic system:
- Verify Concern
- Check System Fuses
- Check Mechanical Condition
- Check Wires and Electrical Connections
- Ensure Data Link Connector Pins Are Okay
- Hook Up Scan Tester
- Perform Data Link Diagnostics
- Repair Communication Network Data Lines (If necessary)
- Retrieve And Record Continuous DTCs
- Clear Continuous DTCs
- Perform On-Demand Self-Test On Selected Module
- Record On-Demand Self-Test DTCs
- Refer To DIAGNOSTIC TROUBLE CODE (DTC) DEFINITIONS
- See Appropriate Articles For Testing Procedures
- See Related WIRING DIAGRAMS
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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