Inspection Procedure 19: Overheating


COMMENT ON TROUBLE SYMPTOM



PROBABLE CAUSE



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code

Q. Is diagnosis code set?
Inspection chart for diagnosis code (Refer to ).
Go to Step 2 .

STEP 2. Check engine coolant.
note If engine coolant level falls too early, check for leaky spots, and repair if necessary.

  • Check engine coolant (Refer to GROUP 14 - On-vehicle Service - Engine Coolant Leak Check ).

Q. Is the check result normal?
Go to Step 3 .
Replace or add engine coolant.

STEP 3. M.U.T.-III actuator test

  • Item 21: Fan controller
OK: Fan motor rotating

Q. Is the check result normal?
Go to Step 4 .
Check fan control relay system (Refer to Inspection Procedure 24 ).

STEP 4. M.U.T.-III data list

  • Item 21: Engine coolant temperature sensor
OK:
    Engine cold state: At ambient temperature (atmospheric temperature) or equivalent.
    Engine hot state: At 80 - 120°C

Q. Is the check result normal?
Go to Step 5 .
Check engine coolant temperature sensor system (Refer to Code No. P0115 ).

STEP 5. Check thermostat.

  • Check thermostat (Refer to GROUP 14 - Thermostat - Thermostat Inspection ).

Q. Is the check result normal?
Go to Step 6 .
Replace thermostat.

STEP 6. Check water pump.

  • Check water pump.

Q. Is the check result normal?
Replace radiator.
Replace water pump.