Diagnostic Procedure For Magnet Clutch

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.

SYMPTOM: Magnet clutch does not engage when A/C switch is ON.

Fig 1: Magnet Clutch - Circuit Diagram

Courtesy of NISSAN NORTH AMERICA, INC.

CHECK INTAKE AND AMBIENT SENSOR CIRCUITS
Check intake and ambient sensors. Refer to "A/C AND AV SWITCH ASSEMBLY SELF-DIAGNOSIS ".

Is the inspection result normal?

YES: GO TO 2.

NO:
- Malfunctioning intake sensor. Refer to "INTAKE SENSOR DIAGNOSIS PROCEDURE ".
- Malfunctioning ambient sensor. Refer to "AMBIENT SENSOR DIAGNOSIS PROCEDURE ".
PERFORM AUTO ACTIVE TEST
Refer to "DIAGNOSIS DESCRIPTION ".

Does magnet clutch operate?

YES:
- WITH CONSULT
  GO TO 5.
- WITHOUT CONSULT
  GO TO 6.
NO: Check 10A fuse (No. 42, located in IPDM E/R), and GO TO 3.
CHECK CIRCUIT CONTINUITY BETWEEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector and compressor (magnet clutch) connector.
3. Check continuity between IPDM E/R harness connector E119 terminal 11 and A/C compressor harness connector F3 terminal 1.
  11 - 1: Continuity should exist.
4. Check continuity between IPDM E/R harness connector E119 terminal 11 and ground.
  11 - ground: Continuity should not exist.
  
  Is the inspection result normal?
  
  YES: GO TO 4.
  
  NO: Repair harness or connector.
CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct current to terminal.

Is the inspection result normal?

YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION OF IPDM E/R ".

NO: Replace magnet clutch. Refer to "REMOVAL AND INSTALLATION FOR COMPRESSOR CLUTCH ".

Fig 2: Checking Magnet Clutch Circuit Operation
Courtesy of NISSAN NORTH AMERICA, INC.
CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to "CONSULT FUNCTION (HVAC) ".

A/C SW ON: COMP ON SIG ON

A/C SW OFF: COMP ON SIG OFF

Is the inspection result normal?

YES: GO TO 8.

NO: GO TO 6.
CHECK CIRCUIT CONTINUITY BETWEEN BCM AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and A/C auto amp. connector.
3. Check continuity between BCM harness connector M18 (A) terminal 27 and A/C auto amp. harness connector M49 (B) terminal 4.
  27 - 4 Continuity should exist.
4. Check continuity between BCM harness connector M18 (A) terminal 27 and ground.
  27 - ground Continuity should not exist.
  
  Fig 3: Checking Continuity Between BCM Harness Connector M18 Terminal 27 And A/C Auto Amp. Connector M49 Terminal 4
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  Is the inspection result normal?
  
  YES: GO TO 7.
  
  NO: Repair harness or connector.

CHECK VOLTAGE FOR A/C AUTO AMP. (A/C COMPRESSOR ON SIGNAL)

Reconnect BCM connector and A/C auto amp. connector.
Turn ignition switch ON.

Check voltage between A/C auto amp. harness connector M49 terminal 4 and ground.

Terminals			Condition	Voltage
(+)		(-)
A/C auto amp. connector	Terminal No.	(-)
M49	4	Ground	A/C switch: ON	Approx. 0V
M49	4	Ground	A/C switch: OFF	Approx. 5V

Fig 4: Checking Voltage Between A/C Auto Amp. Harness Connector M49 Terminal 4 And Ground

Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES: GO TO 8.

NO-1: If the voltage is approx. 5V when A/C switch is ON, replace A/C auto amp. Refer to "REMOVAL AND INSTALLATION ".

NO-2: If the voltage is approx. 0V when A/C switch is OFF, replace BCM. Refer to "REMOVAL AND INSTALLATION ".

CHECK REFRIGERANT PRESSURE SENSOR

Start engine.

Check voltage between ECM harness connector F54 terminal 70 and ground.

Terminals			Condition	Voltage
(+)		(-)
ECM connector	Terminal No.	(-)
F54	70	Ground	A/C switch: ON	Approx. 0.36 - 3.88V

Fig 5: Checking Voltage Between ECM Harness Connector F54 Terminal 70 And Ground

Courtesy of NISSAN NORTH AMERICA, INC.

Is the inspection result normal?

YES: GO TO 9.

NO: Refer to DIAGNOSIS PROCEDURE .

CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to "CONSULT FUNCTION (HVAC) ".

FRONT BLOWER CONTROL DIAL ON: FAN ON SIG ON

FRONT BLOWER CONTROL DIAL OFF: FAN ON SIG OFF

Is the inspection result normal?

YES: GO TO 12.

NO: GO TO 10.
CHECK CIRCUIT CONTINUITY BETWEEN BCM AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect BCM connector and A/C auto amp. connector.
3. Check continuity between BCM harness connector M18 (A) terminal 28 and A/C auto amp. harness connector M49 (B) terminal 5.
  28 - 5 Continuity should exist.
4. Check continuity between BCM harness connector M18 (A) terminal 28 and ground.
  28 - ground Continuity should not exist.
  
  Fig 6: Checking Continuity Between BCM Connector M18 Terminal 28 And A/C Auto Amp. Connector M49 Terminal 5
  Courtesy of NISSAN NORTH AMERICA, INC.
  
  Is the inspection result normal?
  
  YES: GO TO 11.
  
  NO: Repair harness or connector.

CHECK VOLTAGE FOR A/C AUTO AMP. (FAN ON SIGNAL)

Reconnect BCM connector and A/C auto amp. connector.
Turn ignition switch ON.

Check voltage between A/C auto amp. harness connector M49 terminal 5 and ground.

Fig 7: Checking Voltage Between A/C Auto Amp. Harness Connector M49 Terminal 5 And Ground

Courtesy of NISSAN NORTH AMERICA, INC.

Terminals			Condition	Voltage
(+)		(-)
A/C auto amp. connector	Terminal No.	(-)
M49	5	Ground	A/C switch: ON Blower motor operates	Approx. 0V
M49	5	Ground	A/C switch: OFF	Approx. 5V

Is the inspection result normal?

YES: GO TO 12.

NO-1: If the voltage is approx. 5V when blower motor is ON, replace A/C auto amp. Refer to "REMOVAL AND INSTALLATION ".

NO-2: If the voltage is approx. 0V when blower motor is OFF, replace BCM. Refer to "REMOVAL AND INSTALLATION ".

CHECK CAN COMMUNICATION
Check CAN communication. Refer to "SYSTEM DESCRIPTION ".
- BCM - ECM
- ECM - IPDM E/R
- ECM - A/C auto amp.
  Is the inspection result normal?
  
  YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION OF IPDM E/R ".
  
  NO: Repair or replace malfunctioning part(s).