Nissan Pathfinder: Heater & Air Conditioning Control System - Symptom Diagnosis

• Air Conditioner Control-Automatic
• Insufficient Cooling
• Insufficient Heating
• A/c Compressor Does Not Operate

Air Conditioner Control-Automatic Nissan Pathfinder

Symptom Table

NOTE:

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

Symptom		Corresponding malfunction part	Check item/Reference
Air conditioning system does not activate. NOTE: Fail-safe does not activate.		Fuse A/C auto amp. power supply or ground circuit A/C auto amp.	Check A/C auto amp. power supply and ground circuits. Refer to Diagnosis Procedure.
Air conditioning cannot be controlled.	All control	Fuse A/C switch assembly power supply or ground circuit A/C auto amp.	Check A/C switch assembly power supply and ground circuits. Refer to Diagnosis Procedure (front) or Diagnosis Procedure (rear).
	A part of control	A/C switch assembly	Replace A/C switch assembly. Refer to Removal and Installation (front) or Removal and Installation (rear).
A/C switch assembly display or switch indicator lamp does not display correctly.		The results of A/C switch assembly on board diagnosis are normal. Refer to DTC Diagnosis Procedure.
Discharge air temperature (LH side) does not change.		Air mix door motor LH system installation condition	Check air mix door motor LH system is properly installed. Refer to Exploded View.
Discharge air temperature (RH side) does not change.		Air mix door motor RH system installation condition	Check air mix door motor RH system is properly installed. Refer to Exploded View.
Discharge air temperature (rear) does not change.		Air mix door motor (rear) system installation condition	Check air mix door motor (rear) system is properly installed. Refer to Exploded View.
Air outlet does not change.		Mode door motor system installation condition	Check mode door motor system is properly installed. Refer to Exploded View.
Air inlet does not change.		Intake door motor system installation condition	Check intake door motor system is properly installed. Refer to Exploded View.
Front blower motor does not operates or operation speed is not normal.		Fuse Front blower motor Front blower motor power supply or ground circuit Front blower motor control signal circuits A/C auto amp.	Check front blower motor circuits. Refer to Diagnosis Procedure.
A/C compressor does not operate.		Magnetic clutch Magnetic clutch power supply or ground circuit IPDM E/R (smart FET) The circuit between ECM and refrigerant pressure sensor Refrigerant pressure sensor ECM A/C auto amp.	Refer to Diagnosis Procedure.
Insufficient cooling No cool air comes out. (Air flow volume is normal.)		Magnetic clutch control system Drive belt slipping Cooler cycle ECV (Electrical Control Valve) Air leakage from each duct Sunload sensor Temperature setting trimmer	Refer to Diagnosis Procedure.
Insufficient heating No warm air comes out. (Air flow volume is normal.)		Engine cooling system Heater hose Heater core Air leakage from each duct Sunload sensor Temperature setting trimmer	Refer to Diagnosis Procedure.
Noise is heard when the air conditioning operates.	During A/C compressor operation	Cooler cycle	Symptom table for noise Refer to Symptom Table.
	During front blower motor operation	Mixing any foreign object in front blower motor Front blower motor fan breakage Front blower motor rotation inferiority	Check front blower motor. Refer to Component Inspection (Front Blower Motor).

Insufficient Cooling Nissan Pathfinder Fifth generation

Description

Symptom

• Insufficient cooling

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

Diagnosis Procedure

NOTE:

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

CHECK MAGNETIC CLUTCH OPERATION

1. Ignition switch ON.

2. Push fan switch and operate blower fan.

3. Press A/C switch.

4. Check that A/C indicator turns ON. Check visually and by sound that A/C compressor operates.

5. Press A/C switch again.

6. Check that A/C indicator turns OFF. Check that A/C compressor stops.

Is the inspection result normal?

YES>>

GO TO 2.

NO>>

Perform diagnosis of “A/C COMPRESSOR DOES NOT OPERATE” in “SYMPTOM DIAGNOSIS”. Refer to Diagnosis Procedure.

CHECK DRIVE BELT

Check tension of drive belt. Refer to Checking Drive Belt.

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

Adjust or replace drive belt depending on the inspection results.

CHECK REFRIGERANT CYCLE PRESSURE

Connect recovery/recycling recharging equipment to the Nissan Pathfinder vehicle and perform pressure inspection with gauge. Refer to Symptom Table.

Is the inspection result normal?

YES>>

GO TO 4.

NO>>

Repair or replace parts depending on the inspection results.

CHECK ECV

Perform ECV circuit diagnosis. Refer to Diagnosis Procedure.

Is the inspection result normal?

YES>>

GO TO 5.

NO>>

Repair or replace parts depending on the inspection results.

CHECK AIR LEAKAGE FROM EACH DUCT

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

Is the inspection result normal?

YES>>

GO TO 6.

NO>>

Repair or replace parts depending on the inspection results.

CHECK SUNLOAD SENSOR

Perform sunload sensor diagnosis. Refer to Diagnosis Procedure.

Is the inspection result normal?

YES>>

GO TO 7.

NO>>

Repair or replace parts depending on the inspection results.

CHECK SETTING OF TEMPERATURE SETTING TRIMMER

1. Check setting value of temperature setting trimmer. Refer to CONSULT Function.

2. Check that temperature setting trimmer is set to “+ direction”.

   NOTE:

   The control temperature can be set with the setting of the temperature setting trimmer.

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

Is inspection result normal?

YES>>

Inspection End.

NO>>

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

Insufficient Heating Nissan Pathfinder 2022

Description

Symptom

• Insufficient heating

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

Diagnosis Procedure

NOTE:

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

CHECK COOLING SYSTEM

1. Check engine coolant level and check for 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 Refilling.

Is the inspection result normal?

YES>>

GO TO 2.

NO>>

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

CHECK HEATER HOSE

Check installation of heater hose by visually or touching.

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

Repair or replace parts depending on the inspection results.

CHECK HEATER CORE

1. Check temperature of inlet hose and outlet hose of 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?

YES>>

GO TO 4.

NO>>

Replace heater core. Refer to Removal and Installation (front) or Removal and Installation (rear).

CHECK AIR LEAKAGE FROM EACH DUCT

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

Is the inspection result normal?

YES>>

GO TO 5.

NO>>

Repair or replace parts depending on the inspection results.

CHECK SUNLOAD SENSOR

Perform sunload sensor diagnosis. Refer to Diagnosis Procedure.

Is the inspection result normal?

YES>>

GO TO 7.

NO>>

Repair or replace parts depending on the inspection results.

CHECK SETTING OF TEMPERATURE SETTING TRIMMER

1. Check setting value of temperature setting trimmer. Refer to CONSULT Function.

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

   NOTE:

   The control temperature can be set by the temperature setting trimmer.

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

Are the symptoms solved?

YES>>

Inspection End.

NO>>

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

A/c Compressor Does Not Operate Nissan Pathfinder Fifth generation

Description

SYMPTOM

A/C compressor does not operate.

Diagnosis Procedure

NOTE:

• Perform self-diagnoses with CONSULT before performing symptom diagnosis. If any DTC is detected, perform the corresponding diagnosis.

• Check that refrigerant is enclosed in cooler cycle normally. If refrigerant amount is shortage from proper amount, perform the inspection of refrigerant leakage.

CHECK MAGNETIC CLUTCH OPERATION

Check magnetic clutch. Refer to Component Function Check.

Does it operate normally?

YES>>

GO TO 2.

NO>>

Repair or replace malfunctioning parts.

CHECK REFRIGERANT PRESSURE SENSOR

Check refrigerant pressure sensor. Refer to Diagnosis Procedure.

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

Repair or replace malfunctioning parts.

CHECK A/C AUTO AMP. OUTPUT SIGNAL

CONSULT

1. Select “Data Monitor” mode of “HVAC”.

2. Select “COMP REQ SIG” and “FAN REQ SIG”, and check status under the following conditions:

Monitor item	Condition		Status
COMP REQ SIG	A/C switch	OFF (A/C switch indicator: OFF)	Off
		ON (A/C switch indicator: ON)	On
FAN REQ SIG	Front blower motor	OFF	Off
		ON	On

Is the inspection result normal?

YES>>

Replace IPDM E/R. Refer to Removal and Installation.

NO>>

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