Diagnostic Procedure For Intake Sensor

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

SYMPTOM: Intake sensor circuit is open or shorted. (24 or -24 is indicated on unified meter and A/C amp. as a result of performing Self-diagnosis STEP-2.)

Fig 1: Intake Sensor Circuit

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

CHECK VOLTAGE BETWEEN INTAKE SENSOR AND GROUND
1. Disconnect intake sensor connector.
2. Turn ignition switch ON.
3. Check voltage between intake sensor harness connector M256 terminal 1 (R/W) and ground.
  1 - Ground: Approx. 5V
  
  OK or NG
  
  OK: GO TO 2.
  
  NG: GO TO 4.
  
  Fig 2: Checking Intake Sensor Voltage
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between intake sensor harness connector M256 terminal 2 (B/Y) and unified meter and A/C amp. harness connector M51 terminal 49 (B/Y).
  
  Fig 3: Checking Intake Sensor To Unified Meter/A/C Amp Circuit Continuity
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  2 - 49: Continuity should exist.
  
  OK or NG
  
  OK: GO TO 3.
  
  NG: Repair harness or connector.
CHECK INTAKE SENSOR
Refer to INTAKE SENSOR .

OK or NG

OK
1. Replace unified meter and A/C amp.
2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self-diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG
1. Replace intake sensor.
2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self-diagnosis STEP-2. Confirm that code No. 20 is displayed.
CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND UNIFIED METER AND A/C AMP.
1. Turn ignition switch OFF.
2. Disconnect unified meter and A/C amp. connector.
3. Check continuity between intake sensor harness connector M256 terminal 1 (R/W) and unified meter and A/C amp. harness connector M51 terminal 41 (R/Y).
  1 - 41: Continuity should exist.
4. Check continuity between intake sensor harness connector M256 terminal 1 (R/W) and ground.
  
  Fig 4: Checking Intake Sensor To Unified Meter/A/C Amp Circuit Continuity
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  1 - Ground: Continuity should not exist.
OK or NG

OK
1. Replace unified meter and A/C amp.
2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self-diagnosis STEP-2. Confirm that code No. 20 is displayed.
NG: Repair harness or connector.