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.
Monitor Description
The HV control ECU performs many diagnostic tests to verify proper operation of internal and external ECU systems. In one of these diagnostics, the HV control ECU checks the result of the motor main CPU self-test.
If the HV control ECU detects a "Fail" from the motor main CPU self-test, it will conclude that there is an internal malfunction in the motor main CPU. The HV control ECU will illuminate the MIL and set a DTC.
NO RELATED
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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.