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.
Inspection Procedure
HINT:
Troubleshoot each trouble symptom in accordance with the chart below.
| MIL remains illuminated | Start inspection from step 1 |
| MIL not illuminated | Start inspection from step 3 |
- CHECK WHETHER MIL TURNS OFF
- Connect the intelligent tester to the DLC3.
- Turn the ignition switch to the ON position.
- Turn the tester ON.
- Check whether any DTCs have been stored (See DTC CHECK / CLEAR ). Note them down if necessary.
- Clear the DTCs (See DTC CHECK / CLEAR ).
- Check if the MIL turns off.
OK: MIL should turn off.
OK: REPAIR CIRCUIT INDICATED BY OUTPUT DTC
NG: Go to next step
- CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)
- Disconnect the H29 HV control ECU connector.
- Turn the ignition switch to the ON position.
- Check the MIL is not illuminated.
OK: MIL is not illuminated.
- Reconnect the HV control ECU connector.
OK: REPLACE HV CONTROL ECU
NG: CHECK AND REPAIR HARNESS AND CONNECTOR (COMBINATION METER - HV CONTROL ECU)
- CHECK THAT MIL IS ILLUMINATED
- Check if the MIL is illuminated when the ignition switch is turned on.
OK: MIL should be illuminated.
OK: SYSTEM OK
NG: Go to next step
- Check if the MIL is illuminated when the ignition switch is turned on.
- INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT)
- See the combination meter troubleshooting procedure (See PROBLEM SYMPTOMS TABLE ).
NG: REPAIR OR REPLACE BULB OR COMBINATION METER ASSEMBLY
OK: CHECK AND REPAIR HARNESS AND CONNECTOR (COMBINATION METER - HV CONTROL ECU)
Use the Manual With the Right Hardware
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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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