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Inspection Flow

WARNING: This page is about a different car, the 2013 Nissan Armada. However, it is still accessible from the selected car via links, so may be relevant.
  1. CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - TEMPERATURE INCREASE 
    1. Press the AUTO switch.
    2. Turn the temperature control dial (driver) clockwise until 32°C (90°F) is displayed.
    3. Check for hot air at discharge air outlets.

      Can the symptom be duplicated? 

      YES: GO TO 2.

      NO: Perform complete system operational check. Refer to "OPERATIONAL CHECK (FRONT) ".

  2. CHECK FOR SERVICE BULLETINS 

    Check for any service bulletins.

    : GO TO 3.

  3. PERFORM SELF-DIAGNOSIS 

    Perform self-diagnosis. Refer to "A/C AUTO AMP. SELF-DIAGNOSIS ".

    Is the inspection results normal? 

    YES: GO TO 4.

    NO: Refer to "A/C SYSTEM SELF-DIAGNOSIS CODE CHART ".

  4. CHECK ENGINE COOLING SYSTEM 
    1. Check for proper engine coolant level. Refer to "INSPECTION ".
    2. Check hoses for leaks or kinks.
    3. Check radiator cap. Refer to "INSPECTION ".
    4. Check for air in cooling system.

      : GO TO 5.

  5. CHECK AIR MIX DOOR OPERATION 

    Check the operation of the air mix door. Refer to "AIR MIX DOOR MOTOR (DRIVER) COMPONENT FUNCTION CHECK " or "AIR MIX DOOR MOTOR (PASSENGER) COMPONENT FUNCTION CHECK ".

    Is the inspection result normal? 

    YES: GO TO 6.

    NO: Check the air mix door motor circuit. Refer to "AIR MIX DOOR MOTOR (DRIVER) DIAGNOSIS PROCEDURE " or "AIR MIX DOOR MOTOR (PASSENGER) DIAGNOSIS PROCEDURE ".

  6. CHECK AIR DUCTS 

    Check for disconnected or leaking air ducts.

    Is the inspection result normal? 

    YES: GO TO 7.

    NO: Repair all disconnected or leaking air ducts.

  7. CHECK HEATER HOSE TEMPERATURES 
    1. Start engine and warm it up to normal operating temperature.
    2. Touch both the inlet and outlet heater hoses. The inlet hose should be hot and the outlet hose should be warm.

      Is the inspection result normal? 

      YES: Hot inlet hose and a warm outlet hose: GO TO 8.

      NO:

      • Inlet hose cold: GO TO  11.
      • Both hoses warm: GO TO  9.
  8. CHECK ENGINE COOLANT SYSTEM 

    Check engine coolant temperature sensor. Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: System OK.

    NO: Repair or replace as necessary. Retest.

  9. CHECK HEATER HOSES 

    Check heater hoses for proper installation.

    Is the inspection result normal? 

    YES: System OK.

    NO:

    1. Back flush heater core.
    2. Drain the water from the system.
    3. Refill system with new engine coolant. Refer to "CHANGING ENGINE COOLANT ".
    4. GO TO 10 to retest.
  10. CHECK HEATER HOSE TEMPERATURES 
    1. Start engine and warm it up to normal operating temperature.
    2. Touch both the inlet and outlet heater hoses. The inlet hose should be hot and the outlet hose should be warm.

      Is the inspection result normal? 

      YES: System OK.

      NO: Replace heater core. Refer to "REMOVAL AND INSTALLATION ".

  11. CHECK WATER VALVE 

    Check the operation of the water valve. Refer to "WATER VALVE DIAGNOSIS PROCEDURE ".

    Is the inspection result normal? 

    YES: System OK.

    NO: Replace water valve.

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