1.CHECK COOLING SYSTEM

1. Check engine coolant level and check for leakage. Refer to Inspection.
2. Check radiator cap. Refer to Inspection.
3. Check water flow sounds of engine coolant. Refer to Refilling.

Is the inspection result normal?
YES>>GO TO 2.
NO>>Refill the engine coolant and repair or replace the parts according to the inspection results.
2.CHECK OPERATION

1. Turn temperature dial (driver side) and raise temperature setting to 32.0°C (90°F) after warming up the engine.
2. Check that warm air blows from the outlets.

Is the inspection result normal?
YES>>INSPECTION END
NO>>GO TO 3.
3.CHECK SETTING OF TEMPERATURE SETTING TRIMMER
With CONSULT-III

1. Select “TEMP SET CORRECT” of HVAC work support item. Refer to Temperature Setting Trimmer.
2. Check that the temperature setting trimmer is set to “− direction”.
   NOTE：
   The control temperature can be set by the temperature setting trimmer.
3. Set the difference between the set temperature and control temperature to “0”.

Are the symptoms solved?
YES>>INSPECTION END
NO>>GO TO 4.
4.CHECK SELF-DIAGNOSIS RESULT CHECK
With CONSULT-III

1. Perform the “SELF-DIAGNOSIS”.
2. Check if any DTC is detected in the self-diagnostic results.
   NOTE：
   If DTC is displayed along with DTC U1000 or U1010, first diagnose the DTC U1000 or U1010. Refer to DTC Logic or DTC Logic.

Is any DTC displayed?
YES>>Perform the diagnosis that is applicable to the sensor and the door motor. Refer to DTC Index.
NO>>GO TO 5.
5.CHECK EACH OUTPUT DEVICE
With CONSULT-III

1. Select “HVAC TEST” of HVAC active test item. Refer to CONSULT-III Function.
   NOTE：
   Perform the ACTIVE TEST after starting the engine because the compressor is operated.
2. Refer to the table and check the outlet, inlet, air flow 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
   MODE 1 | MODE 2 | MODE 3 | MODE 4 | MODE 5 | MODE 6 | MODE 7
   Mode door position | VENT | B/L 1 | B/L 2 | 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 fan motor control signal duty ratio | 37% | 91% | 65% | 65% | 65% | 91% | —
   Magnetic clutch | ON | ON | OFF | OFF | ON | ON | —
   ECV | 100% | 100% | 0% | 0% | 50% | 100% | —
   NOTE：
   - Perform the inspection of each output device after starting the engine because the compressor is operated.
   - If the MODE 7 is selected, the malfunction is displayed but it is normal.

Does it operate normally?
YES>>GO TO 6.
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 (driver side). Refer to Diagnosis Procedure.
NO‐4>>Discharge air temperature does not change (passenger side). Refer to Diagnosis Procedure.
>>Blower motor does not operate normally. Refer to Diagnosis Procedure.
NO‐5>>Magnet clutch does not operate. Refer to Diagnosis Procedure.
6.CHECK AIR LEAKAGE FROM DUCT
Check duct and nozzle, etc. of the air conditioner system for air leakage.
Is the inspection result normal?
YES>>GO TO 7.
NO>>Repair or replace parts according to the inspection results.
7.CHECK HEATER HOSE INSTALLATION CONDITION
Check the heater hose installation condition visually (for twists, crushes, etc.).
Is the inspection result normal?
YES>>GO TO 8.
NO>>Repair or replace parts according to the inspection results.
8.CHECK TEMPERATURE OF HEATER HOSE

1. Check the temperature of inlet hose and outlet hose of heater core.
2. Check that the inlet side of heater core is hot and the outlet side is slightly lower than/almost equal to the inlet side.
   ■ CAUTION ■
   Always perform the temperature inspection in a short period of time because the engine coolant temperature is very hot.

Is the inspection result normal?
YES>>GO TO 9.
NO>>Replace the heater core after performing the procedures after the cooling system inspection. GO TO 1.
9.REPLACE HEATER CORE
Replace the heater core. Refer to heater core. Refer to Exploded View (GT-R certified NISSAN dealer).
Are symptoms solved?
YES>>INSPECTION END
NO>>Perform the procedures again after the cooling system inspection. GO TO 1.