Magnet Clutch Circuit

WARNING: This page is about a different car, the 2004 Nissan Sentra. 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 and fan control switch are ON.

CHECK POWER SUPPLY FOR COMPRESSOR
Disconnect compressor harness connector.

Do approx. 12 volts exist between compressor harness connector E36 terminal 1, (L/R) and body ground?

Fig 1: Checking Power Supply For Compressor
Courtesy of NISSAN MOTOR CO., U.S.A.

Yes or No
1. Yes: GO TO 2.
2. No: GO TO 3.
CHECK MAGNET CLUTCH COIL
Disconnect magnet clutch connector.

Do approx. 3.2Ω exist between A/C compressor harness connector E36 terminal 1, (L/R) and body ground?

Fig 2: Checking Magnet Clutch Coil
Courtesy of NISSAN MOTOR CO., U.S.A.

Yes or No
1. Yes: INSPECTION END.
2. No: Replace magnet clutch. Refer to "COMPRESSOR CLUTCH ".
CHECK CIRCUIT CONTINUITY BETWEEN A/C RELAY AND COMPRESSOR HARNESS
Disconnect A/C relay.

Check circuit continuity between A/C relay harness terminal 3 and compressor harness terminal 1.

Fig 3: Checking Circuit Continuity Between A/C Relay And Compressor Harness
Courtesy of NISSAN MOTOR CO., U.S.A.

If OK, check harness for short.

OK or NG
1. OK: GO TO 4.
2. NG: Repair harness or connector.
CHECK INTAKE SENSOR CIRCUIT
Refer to "INTAKE SENSOR CIRCUIT ".

OK or NG
1. OK: GO TO 5.
2. NG: Repair as necessary.
CHECK POWER SUPPLY FOR A/C RELAY
Disconnect A/C relay.

Do approx. 12 volts exist between A/C relay harness terminal 1, 5 and body ground?

Fig 4: Checking Power Supply For A/C Relay
Courtesy of NISSAN MOTOR CO., U.S.A.

Yes or No
1. Yes: GO TO 6.
2. No: Check power supply circuit and 10A (No. 15) fuse at fuse block. Refer to FUSES & CIRCUIT BREAKERS - SENTRA .
CHECK A/C RELAY AFTER DISCONNECTING IT
Refer to "A/C RELAY ".

OK or NG
1. OK: Reconnect A/C relay. GO TO 7.
2. NG: Replace A/C relay.
CHECK COIL SIDE CIRCUIT OF A/C RELAY
Reconnect A/C relay.

Do approx. 12 volts exist between ECM harness connector F59 terminal 105 (L) and body ground?

Battery voltage should exist.

Yes or No
1. Yes: GO TO 9.
2. No: Disconnect A/C relay. Disconnect ECM harness connector. GO TO 8.
  
  Fig 5: Checking Coil Side Circuit Of A/C Relay
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK CIRCUIT CONTINUITY BETWEEN A/C RELAY AND ECM HARNESS
Check circuit continuity between A/C relay harness connector E50 terminal 2 (L) and ECM harness connector F59 terminal 105 (L).

Continuity should exist.

If OK, check harness for short.

OK or NG
1. OK: Check ECM.
2. NG: Repair harness or connector.
  
  Fig 6: Checking Circuit Continuity Between A/C Relay And ECM Harness
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK VOLTAGE FOR ECM
Do approx. 12 volts exist between ECM harness connector F59 terminal No. 110 (L/R) and body ground?

Battery voltage should exist.

Yes or No
1. Yes: GO TO 10.
2. No: Check ECM.
  
  Fig 7: Checking Voltage For ECM
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK REFRIGERANT PRESSURE SENSOR
Refer to "REFRIGERANT PRESSURE SENSOR ".

OK or NG
1. OK: GO TO 11.
2. NG: Replace refrigerant pressure sensor.
CHECK CIRCUIT CONTINUITY BETWEEN FAN CONTROL SWITCH AND A/C CONTROL UNIT
Disconnect A/C control unit and fan control switch.

Check circuit continuity between fan control switch harness connector M31 terminal No. 6 (Y/G) and A/C control unit harness connector M32 terminal No. 8 (Y/G).

Continuity should exist.

If OK, check harness for short.

OK or NG
1. OK: GO TO 12.
2. NG: Repair harness or connector.
  
  Fig 8: Checking Circuit Continuity Between Fan Control Switch And A/C Control Unit
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK FAN CONTROL SWITCH GROUND
Disconnect fan control switch harness connector.

Does continuity exist between fan control switch harness terminal No. 5 and body ground?

Fig 9: Checking Fan Control Switch Ground
Courtesy of NISSAN MOTOR CO., U.S.A.

Yes or No
1. Yes: Replace A/C control unit.
2. No: Repair harness or connector.