Nissan Murano: Heater & Air Conditioning Control System :: Symptom Diagnosis / Insufficient Heating

Diagnosis Procedure

Symptom

• Insufficient heating.

• No warm air comes out. (Air flow volume is normal.)

NOTE:

Perform self-diagnoses with on board diagnosis and CONSULT before performing symptom diagnosis. If DTC is detected, perform the corresponding diagnosis.

CHECK COOLING SYSTEM

1. Check engine coolant level and check leakage. Refer to System Inspection.

2. Check reservoir tank cap. Refer to System Inspection.

3. Check water flow sounds of the engine coolant. Refer to System Inspection.

Is the inspection result normal?

GO TO 2.

Refill engine coolant and repair or replace parts depending on the inspection results.

CHECK HEATER HOSE

Check installation of heater hose visually or by touching.

Is the inspection result normal?

GO TO 3.

Repair or replace parts depending on the inspection results.

CHECK HEATER CORE

1. Check temperature of inlet hose and outlet hose of front heater core.

2. Check that 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?

GO TO 4.

Replace heater core. Refer to Removal and Installation.

CHECK AIR LEAKAGE FROM EACH DUCT

Check duct and nozzle, etc. of front air conditioning system for air leakage.

Is the inspection result normal?

GO TO 5.

Repair or replace parts depending on the inspection results.

CHECK SETTING OF TEMPERATURE SETTING TRIMMER (FRONT)

1. Check setting value of temperature setting trimmer (front). Refer to Temperature Setting Trimmer (Front).

2. Check that temperature setting trimmer (front) is set to “− direction”.

   NOTE:

   The control temperature can be set by the temperature setting trimmer (front).

3. Set difference between the set temperature and control temperature to “0”.

Are the symptoms solved?

Inspection End.

Replace A/C auto amp. Refer to Removal and Installation.