Diagnostic Procedure For Optical Sensor

WARNING: This page is about a different car, the 2006 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM: Optical sensor circuit is open or shorted. Using the CONSULT-II, DTC B257F or B2580 is displayed. Without a CONSULT-II, code 50 or 52 is indicated on front air control as a result of conducting the front air control self-diagnosis.

Fig 1: Optical Sensor - Communication Diagram

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

CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect front air control connector and optical sensor connector.
3. Check continuity between optical sensor harness connector M402 terminal 1 and 2 and front air control harness connector M50 terminal 40 and 31.
  Continuity should exist.
4. Check continuity between optical sensor harness connector M402 terminal 1 and 2 and ground.
  Continuity should not exist.
  
  Fig 2: Checking Circuit Continuity Between Optical Sensor And Front Air Control
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK : GO TO 2.

NG : Repair harness or connector.
CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND BCM
1. Disconnect BCM connector.
2. Check continuity between optical sensor harness connector (B) M402 terminal 3 and BCM harness connector (A) M18 terminal 18.
  Continuity should exist.
3. Check continuity between optical sensor harness connector M402 terminal 3 and ground.
  Continuity should not exist.
  
  Fig 3: Checking Circuit Continuity Between Optical Sensor And BCM
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG

OK : Replace optical sensor. Refer to "OPTICAL SENSOR "

NG : Repair harness or connector.