Diagnostic Procedure

WARNING: This page is about a different car, the 2003 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

CHECK POWER SUPPLY FOR AUTO AMP. (LCU) SIDE

Fig 1: Checking Auto Amp. (LCU) Side Power Supply (1 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 2: Checking Auto Amp. (LCU) Side Power Supply (2 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 2.
2. NG: Replace auto amp. (LCU).
CHECK SIGNAL FOR AUTO AMP. (LCU) SIDE

Fig 3: Checking Auto Amp. (LCU) Side Signal (1 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 4: Checking Auto Amp. (LCU) Side Signal (2 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 3.
2. NG: Replace auto amp. (LCU).
CHECK POWER SUPPLY FOR MOTOR SIDE

Fig 5: Checking Motor Side Power Supply (1 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 6: Checking Motor Side Power Supply (2 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 4.
2. NG: Replace harness or connector.
CHECK SIGNAL FOR MOTOR SIDE

Fig 7: Checking Motor Side Signal (1 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 8: Checking Motor Side Signal (2 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 5.
2. NG: Replace harness or connector.
CHECK MOTOR GROUND CIRCUIT

Fig 9: Checking Motor Ground Circuit (1 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 10: Checking Motor Ground Circuit (2 Of 2)
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 6.
2. NG: Replace harness or connector.
CHECK MOTOR OPERATION
Disconnect and reconnect the motor connectors and confirm the motor operation.

OK or NG
1. OK: (Return to operate normally.)
  - Poor contacting the motor connector
2. NG: (Does not operate normally.)
  - GO TO 7.
CHECK MODE DOOR MOTOR AND AIR MIX DOOR MOTOR OPERATION
1. Disconnect the intake door motor connector.
2. Reconnect the mode door motor connector and air mix door motor connector, confirm the mode door motor and air mix door motor operation.
OK or NG
1. OK: (Mode door motor and air mix door motor operate normally.)
  - Replace the intake door motor.
2. NG: (Mode door motor and air mix door motor do not operate normally.)
  - GO TO 8.
CHECK AIR MIX DOOR MOTOR AND INTAKE DOOR MOTOR OPERATION
1. Disconnect mode door motor connector.
2. Reconnect the intake door motor connector, confirm the air mix door motor and intake door motor operation.
OK or NG
1. OK: (Air mix door motor and intake door motor operate normally.)
  - Replace mode door motor.
2. NG: (Air mix door motor and intake door motor do not operate normally.)
  - GO TO 9.
CHECK INTAKE DOOR MOTOR AND MODE DOOR MOTOR OPERATION
1. Disconnect air mix door motor connector.
2. Reconnect mode door motor connector, confirm the intake door motor and mode door motor operation.
OK or NG
1. OK: (Intake door motor and mode door motor operate normally.)
  - Replace air mix door motor.
2. NG: (Intake door motor and mode door motor do not operate normally.)
  - Replace auto amp.