Your Vehicle: 2009 Nissan-Datsun Altima V6-3.5L (VQ35DE)
 
Vehicle » Heating and Air Conditioning » Testing and Inspection » Component Tests and General Diagnostics » Magnet Clutch » Diagnosis Procedure » Automatic Air Conditioner  
 
 
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MAGNET CLUTCH

Description

SYSTEM DESCRIPTION
Front air control controls A/C compressor operation by ambient temperature and signal from ECM.

Low Temperature Protection Control
Front air control will turn the A/C compressor ON or OFF as determined by a signal detected by ambient sensor.

  

When ambient temperature is greater than -2°C (28°F) , the A/C compressor turns ON. The A/C compressor turns OFF when ambient temperature is less than -5°C (23°F) .

MAGNET CLUTCH

Diagnosis Procedure

DIAGNOSIS PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.

  

1.CHECK POWER SUPPLY FOR A/C COMPRESSOR

  1. Disconnect A/C compressor connector.

  

  1. Start engine and press A/C switch.
  2. Check voltage between A/C compressor harness connector F3 terminal 1 and ground.

  

Is the Inspection result normal?
YES >> Check magnet clutch coil.

  1. If NG, replace magnet clutch. Refer to See: Compressor HVAC\Service and Repair.
  2. If OK, check A/C compressor mounting points for looseness or corrosion and repair as necessary. NO >> GO TO 2

2.CHECK CIRCUIT CONTINUITY BETWEEN A/C RELAY IN IPDM E/R AND A/C COMPRESSOR

  

  1. Disconnect IPDM E/R connector F10 and A/C compressor connector F3.
  2. Check continuity between A/C compressor harness connector F3 (A) terminal 1 and IPDM E/R harness connector F10 (B) terminal 48.

  

If OK, check harness for short to ground.
Is the Inspection result normal?
YES >> GO TO 3
NO >> Repair harness or connector.
3.CHECK FUSE IN IPDM E/R
Check 10A fuse (No. 41 located in the IPDM E/R).
Is the Inspection result normal?
YES >> GO TO 4
NO >> Replace fuse and check IPDM E/R for short circuit. Replace if necessary.
4.CHECK A/C COMPRESSOR ON SIGNAL

  

Check voltage between front air control connector M37 terminal 5 and ground, with A/C compressor ON and with A/C compressor
OFF.

  

Is the Inspection result normal?
YES >> GO TO 5
NO >>

  • When A/C compressor is ON and voltage is not approx. 0V, Replace front air control. Refer to See: Control Module HVAC\Service and Repair.
  • When A/C compressor is OFF and voltage is not approx. 5V, BCM is malfunctioning. 5.CHECK CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL

  

  1. Disconnect BCM connector M18 and front air control connector.
  2. Check continuity between BCM harness connector M18 (A) terminal 33 and front air control connector M37 (B) terminal 5.

  

Is the Inspection result normal?
YES >> GO TO 6
NO >> Repair harness or connector.
6.CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL

  

  1. Reconnect all disconnected connectors.
  2. Start the engine.
  3. Check voltage between ECM harness connector F13 terminal 39 and ground.

  

Is the Inspection result normal?
YES >> GO TO 7
NO >> 1. Repair harness or connector.

  1. Confirm that magnet clutch operation is normal. 7.CHECK REFRIGERANT PRESSURE SENSOR

Refer to (QR25DE) or See: Powertrain Management\Computers and Control Systems\Testing and Inspection\Component Tests and General Diagnostics\Refrigerant Pressure Sensor\Diagnosis Procedure(VQ35DE).
Is the Inspection result normal?
YES >> GO TO 8
NO >> Replace refrigerant pressure sensor. Refer to See: Refrigerant Pressure Sensor / Switch\Service and Repair.
8.CHECK CAN COMMUNICATION CIRCUITS
Check CAN communication circuits between BCM to ECM and between ECM to IPDM E/R. Refer to See: Powertrain Management\Computers and Control Systems\Information Bus\Testing and Inspection\Scan Tool Testing and Procedures.
Is the Inspection result normal?
YES >> ECM malfunctioning.
NO >> Repair or replace component based on the result of diagnosis.