Diagnostic Procedure For Magnet Clutch

WARNING: This page is about a different car, the 2004 Nissan Quest. 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: Identifying Magnet Clutch Circuit

Courtesy of NISSAN MOTOR CO., U.S.A.

CHECK INTAKE SENSOR CIRCUIT
Check intake sensor. Refer to "A/C SYSTEM SELF-DIAGNOSIS FUNCTION ".

OK or NG
1. OK: GO TO 2.
2. NG: Malfunctioning intake sensor. Refer to "INTAKE SENSOR CIRCUIT ".
PERFORM AUTO ACTIVE TEST
Refer to "AUTO ACTIVE TEST ".

Does magnet clutch operate?

Yes or No
1. Yes :
  - WITH CONSULT-II GO TO 5.
  - WITHOUT CONSULT-II GO TO 6.
2. No: Check 10A fuse (No. 34, 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 E124 terminal 33 (Y/B) and compressor harness connector F3 terminal 1 (Y/B).
  33-1: Continuity should exist.
  
  OK or NG
  1. OK: GO TO 4.
  2. NG: Repair harness or connector.
    
    Fig 2: Checking Continuity Between IPDM E/R Harness Connector E124 Terminal 33 (Y/B) And Compressor Harness Connector F3 Terminal 1 (Y/B)
    Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct current to terminal.

OK or NG
1. OK: Replace IPDM E/R.
2. NG: Replace magnet clutch. Refer to "REMOVAL AND INSTALLATION FOR COMPRESSOR CLUTCH ".
  
  Fig 3: Applying Battery Voltage Direct Current To Terminal
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to "CONSULT-II ".

A/C SW ON: COMP ON SIG ON

A/C SW OFF: COMP ON SIG OFF

OK or NG
1. OK: GO TO 8.
2. NG: GO TO 6.
  
  Fig 4: Consult-II Display (DATA MONITOR)
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect BCM connector and front air control connector.
3. Check continuity between BCM harness connector M18 terminal 27 (L/R) and front air control harness connector M49 terminal 12 (L/R).
  Continuity should exist.
  
  OK or NG
  1. OK: GO TO 7.
  2. NG: Repair harness or connector.
    
    Fig 5: Check Continuity Between BCM Harness Connector M18 Terminal 27 (L/R) And Front Air Control Harness Connector M49 Terminal 12 (L/R)
    Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK VOLTAGE FOR FRONT AIR CONTROL (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and front air control connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M49 terminal 12 (L/R) and ground.
  
  Fig 6: Front Air Control Harness Connector M49 Terminal 12 Voltage Specifications
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 7: Checking Voltage Between Front Air Control Harness Connector M49 Terminal 12 (L/R) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
  1. OK: GO TO 8.
  2. NG-1: If the voltage is approx. 5V when A/C switch is ON, replace front air control.
  3. NG-2: If the voltage is approx. OV when A/C switch is OFF, replace BCM.
CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start engine.
2. Check voltage of refrigerant pressure sensor. Refer to "CONSULT-II ".
WITHOUT CONSULT-II
1. Start engine.
2. Check voltage between ECM harness connector F54 terminal 70 (W) and ground.
  
  Fig 8: ECM Harness Connector F54 Terminal 70 Voltage Specifications
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 9: Checking Voltage Between ECM Harness Connector F54 Terminal 70 (W) And Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  OK or NG
  1. OK :
    - WITH CONSULT-II GO TO 9.
    - WITHOUT CONSULT-II GO TO 4.
  2. NG: Refer to "REFRIGERANT PRESSURE SENSOR ".
3. CHECK BCM INPUT (FAN ON) SIGNAL
  Check FAN ON/OFF signal. Refer to "CONSULT-II ".
  
  FAN CONTROL SWITCH ON: FAN ON SIG ON
  
  FAN CONTROL SWITCH OFF: FAN ON SIG OFF
  
  OK or NG
  1. OK: GO TO 6.
  2. NG: GO TO 10.
    
    Fig 10: Consult-II Display (DATA MONITOR)
    Courtesy of NISSAN MOTOR CO., U.S.A.
4. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL
  1. Turn ignition switch OFF.
  2. Disconnect BCM connector and front air control connector.
  3. Check continuity between BCM harness connector M18 terminal 28 (G/B) and front air control harness connector M49 terminal 26 (G/B).
    Continuity should exist.
    
    OK or NG
    1. OK: GO TO 11.
    2. NG: Repair harness or connector.
      
      Fig 11: Checking Continuity Between BCM Harness Connector M18 Terminal 28 (G/B) And Front Air Control Harness Connector M49 Terminal 26 (G/B)
      Courtesy of NISSAN MOTOR CO., U.S.A.
5. CHECK VOLTAGE FOR FRONT AIR CONTROL (FAN ON SIGNAL)
  1. Reconnect BCM connector and front air control connector.
  2. Turn ignition switch ON.
  3. Check voltage between front air control harness connector M49 terminal 26 (G/B) and ground.
    
    Fig 12: Front Air Control Harness Connector M49 Terminal 26 Voltage Specifications
    Courtesy of NISSAN MOTOR CO., U.S.A.
    
    Fig 13: Checking Voltage Between Front Air Control Harness Connector M49 Terminal 26 (G/B) And Ground
    Courtesy of NISSAN MOTOR CO., U.S.A.
    
    OK or NG
    1. OK: GO TO 12.
    2. NG-1: If the voltage is approx. 5V when blower motor is ON, replace front air control.
    3. NG-2: If the voltage is approx. 0V when blower motor is OFF, replace BCM. Refer to "REMOVAL AND INSTALLATION OF BCM ".
6. CHECK CAN COMMUNICATION
  Check CAN communication. Refer to "CAN COMMUNICATION SYSTEM DESCRIPTION ".
  - BCM - ECM
  - ECM - IPDM E/R
  - ECM - Front air control
  OK or NG
  1. OK: INSPECTION END.
  2. NG: Repair or replace malfunctioning part(s).