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Inspection Procedure

HINT:

Troubleshoot each trouble symptom in accordance with the chart below.

TROUBLESHOOT CHART

MIL remains illuminated Start inspection from step 1
MIL not illuminated Start inspection from step 3
  1. CHECK WHETHER MIL TURNS OFF 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch to the ON position.
    3. Turn the tester ON.
    4. Check whether any DTCs have been stored (See DTC CHECK / CLEAR  ). Note them down if necessary.
    5. Clear the DTCs (See DTC CHECK / CLEAR  ).
    6. Check if the MIL turns off.

      OK: MIL should turn off. 

    OK: REPAIR CIRCUIT INDICATED BY OUTPUT DTC 

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) 
    1. Disconnect the H29 HV control ECU connector.
    2. Turn the ignition switch to the ON position.
    3. Check the MIL is not illuminated.

      OK: MIL is not illuminated. 

    4. Reconnect the HV control ECU connector.
    5. Fig 1: Identifying Terminals Of H29 HV Control ECU Connector
      G05275757Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE HV CONTROL ECU 

    NG: CHECK AND REPAIR HARNESS AND CONNECTOR (COMBINATION METER - HV CONTROL ECU) 

  3. CHECK THAT MIL IS ILLUMINATED 
    1. 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 

  4. INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT) 
    1. 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)