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Inspection Flow

WARNING: This page is about a different car, the 2009 Nissan Maxima. However, it is still accessible from the selected car via links, so may be relevant.
  1. CONFIRM SYMPTOM BY PERFORMING OPERATION CHECK - TEMPERATURE DECREASE
    1. Press the AUTO switch.
    2. Turn temperature control switch (driver side) counterclockwise until 18°C (60°F) is displayed.
    3. Check for cold air at discharge air outlets.

    Can a symptom be duplicated? 

    YES: GO TO  3

    NO: GO TO 2

  2. CHECK FOR ANY SYMPTOMS

    Perform a complete operational check and check for any symptoms. Refer to "OPERATIONAL CHECK ".

    Does another symptom exist? 

    YES: Refer to "WITH MONOCHROME DISPLAY: SYMPTOM MATRIX CHART ".

    NO: System OK.

  3. CHECK FOR SERVICE BULLETINS

    Check for any service bulletins.

    GO TO 4

  4. CHECK DRIVE BELTS

    Check A/C compressor belt tension. Refer to "CHECKING DRIVE BELTS ".

    Is the inspection result normal? 

    YES: GO TO 5

    NO: Adjust or replace A/C compressor belt. Refer to "REMOVAL AND INSTALLATION ".

  5. CHECK SETTING OF TEMPERATURE SETTING TRIMMER

    Using CONSULT-III, check the setting of "TEMP SET CORRECT" on "WORK SUPPORT" of HVAC. Refer to "TEMPERATURE SETTING TRIMMER ".

    1. Check that the temperature setting trimmer is set to "+ direction".
      NOTE: The control temperature can be set with the setting of the temperature setting trimmer.
    2. Set temperature control dial to "0".

    Is the symptom still present? 

    YES: GO TO 6.

    NO: Inspection End.

  6. CHECK WITH SELF-DIAGNOSIS FUNCTION OF CONSULT-III
    1. Using CONSULT-III, perform "SELF-DIAGNOSIS RESULTS" of HVAC.
    2. Check if any DTC No. is displayed in the trouble diagnosis results.
    NOTE: If DTC is displayed along with DTC U1000 or U1010, first diagnose the DTC U1000 or U1010. Refer to "DTC LOGIC - U1000 CAN COMM CIRCUIT " or "DTC LOGIC - U1010 CONTROL UNIT (CAN) ".

    Is any DTC No. displayed? 

    YES: Perform diagnosis for the applicable DTC. Refer to "DTC INDEX ".

    NO: GO TO 7.

  7. CHECK WITH ACTIVE TEST OF CONSULT-III
    1. Using CONSULT-III, perform "HVAC TEST" "ACTIVE TEST" of HVAC to check each output device. Refer to "CONSULT-III FUNCTION ".
      NOTE: Perform the ACTIVE TEST after starting the engine because the A/C compressor is operating.
    2. Refer to the table and check the outlet, inlet, airflow temperature, blower motor control signal, magnet clutch operation, and air mix ratio. Visually check each operating condition, by listening for noise, touching air outlets with a hand, etc.
    TEST ITEM CHART

      Test item
    MODE 1 MODE 2 MODE 3 MODE 4 MODE 5 MODE 6
    Mode door position VENT1 B/L1 B/L2 FOOT D/F DEF
    Intake door position REC REC 20%FRE FRE FRE FRE
    Air mix door position (driver & passenger side) FULL COLD FULL COLD FULL HOT FULL HOT FULL HOT FULL HOT
    Blower motor duty ratio 37% 91% 65% 65% 65% 91%
    A/C compressor (Magnet clutch) ON ON ON OFF ON ON

    Does it operate normally? 

    YES: GO TO 8.

    NO-1: Air outlet does not change. Refer to "DIAGNOSIS PROCEDURE ".

    NO-2: Air inlet does not change. Refer to "DIAGNOSIS PROCEDURE ".

    NO-3: Discharge air temperature does not change. Refer to "DIAGNOSIS PROCEDURE - B2632, B2633 AIR MIX DOOR MOTOR (DRIVER SIDE) " and "DIAGNOSIS PROCEDURE - B2634, B2635 AIR MIX DOOR MOTOR (PASSENGER SIDE) ".

    NO-4: Blower motor does not operate normally. Refer to "DIAGNOSIS PROCEDURE ".

    NO-5: Magnet clutch does not operate. Refer to "DIAGNOSIS PROCEDURE ".

  8. CHECK AIR MIX DOOR MOTOR OPERATION

    Check and verify air mix door mechanism for smooth operation.

    Does air mix door operate correctly? 

    YES: GO TO 9

    NO: Repair or replace air mix door control linkage.

  9. CHECK COOLING FAN MOTOR OPERATION

    Check and verify cooling fan motor for smooth operation.

    Does cooling fan motor operate correctly? 

    YES: GO TO 10

    NO: Check cooling fan motor. Refer to "COMPONENT INSPECTION (COOLING FAN MOTOR) ".

  10. CHECK RECOVERY/RECYCLING EQUIPMENT BEFORE USAGE

    Check recovery/recycling equipment before connecting to vehicle. Verify there is no pressure in the recovery/recycling equipment by checking the gauges. If pressure exists, recover refrigerant from equipment lines.

    GO TO 11

  11. CHECK REFRIGERANT PURITY
    1. Connect recovery/recycling equipment to vehicle.
    2. Confirm refrigerant purity in supply tank using recovery/recycling and refrigerant unidentified.

    Is the inspection result normal? 

    YES: GO TO 12

    NO: Check contaminated refrigerant. Refer to "COLLECTION AND CHARGE ".

  12. CHECK REFRIGERANT PRESSURE

    Check refrigerant pressure with manifold gauge connected. Refer to "PERFORMANCE CHART ".

    Is the inspection result normal? 

    YES: Perform diagnostic work flow. Refer to "DIAGNOSTIC WORK FLOW ".

    NO: GO TO 13

  13. CHECK FOR EVAPORATOR FREEZE-UP

    Start engine and run A/C. Check for evaporator freeze-up.

    NOTE: Evaporator freeze up usually occurs at sustained highway speeds in hot, humid conditions with blend door at full-cold and blower on low speed, after 1-3 hours of continuous driving.

    Does evaporator freeze up? 

    YES: Perform diagnostic work flow. Refer "DIAGNOSTIC WORK FLOW ".

    NO: GO TO 14

  14. CHECK AIR DUCTS

    Check ducts for air leaks.

    Is the inspection result normal? 

    YES: System OK.

    NO: Repair air leaks.

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