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.
KOER On-Demand Self-Test: Description
KOER on-demand self-test is a functional test of PCM performed with ignition key on, engine running. A check of certain inputs and outputs is made during operating conditions and normal operating temperature. The brake pedal position, transmission control and power steering switch tests are part of KOER on-demand self-test and must be performed during this operation (if applicable). A fault must be present at time of testing for KOER on-demand self-test to detect a fault.
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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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