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.
Key On, Engine Running (KOER) Self-Test
1) Deactivate self-test. Start and run engine at 2000 RPM for 2 minutes to warm up O2S. Turn off engine and wait 10 seconds.
2) Restart engine, and activate self-test. Record all service codes displayed. See TROUBLE CODE IDENTIFICATION table. If no codes are present, proceed to SWITCH MONITOR TEST.
NO RELATED
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.