COOLING FAN ECU ON-VEHICLE INSPECTION

PROCEDURE


  1. INSPECT COOLING FAN ECU


    1. Check and ensure the following conditions:


      1. The power switch is off.

      2. The engine coolant temperature is less than 92°C (198°F).

      3. The auxiliary battery voltage is between 11 to 14 V.

      4. The A/C switch is off.

    2. Connect the pickup of a clamp-on ammeter around either of the 2 wires for the cooling fan motor.

    3. Put the engine in inspection mode (maintenance mode).

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    4. Turn the power switch on (IG) and wait for approximately 10 seconds. Check that the cooling fans are not operating.

    5. Start the engine. Check that the cooling fans are not operating with the engine idling.

      Tech Tips


      • Make sure that the engine coolant temperature is less than 92°C (198°F).


      • Turn the A/C switch off.

    6. Check that the cooling fans operate when the A/C switch is turned on.

    7. Measure the current while the cooling fan motors are turning.

      Standard Current
      Item Condition Specified Condition
      Cooling fan motor Auxiliary battery voltage applied at 20°C (68°F) 13.0 to 19.0 A
      No. 2 cooling fan motor 13.0 to 19.0 A

      Tech Tips

      The engine coolant temperature should be less than 92°C (198°F).

    8. Check that the cooling fans operate when the engine coolant temperature sensor connector is disconnected.

    9. Measure the current while the cooling fan motors are turning.

      Standard Current
      Item Condition Specified Condition
      Cooling fan motor Auxiliary battery voltage applied at 20°C (68°F) 13.0 to 19.0 A
      No. 2 cooling fan motor 13.0 to 19.0 A
    10. A01OABYC14
      *a Operating Diagram
      *b MAX HI
      *c HI
      *d LO
      *e OFF
      *f Fan Speed

      After the engine is warmed up, check that the cooling fans operate as shown in the illustration.

      Tech Tips


      • The engine coolant temperature at which the fans start operating is approximately 94°C (201°F).

      • This system can also be checked using the GTS.

      • Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.


      Powertrain > Engine > Data List
      Tester Display
      Coolant Temp