Diagnostic Procedure For Intake Sensor

WARNING: This page is about a different car, the 2004 Infiniti FX45 and 2004 Infiniti FX35. 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.)

Fig 1: Displaying 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 M254 terminal 2 (R) and ground.
  1. 2 - Ground : Approx. 5V
Fig 2: Checking Intake Sensor & Ground Voltage
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 2 .
2. NG: GO TO 4 .
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 M254 terminal 1 (W) and unified meter and A/C amp. harness connector M57 terminal 49 (W/G).
  1. 1 - 49 : Continuity should exist.
Fig 3: Checking Intake Sensor-to-Unified Meter & A/C Amp. Circuit Continuity
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 3 .
2. NG: Repair harness or connector.
Check Intake Sensor
Refer to INTAKE SENSOR .

OK or NG
1. OK:
  1. Replace unified meter and A/C amp.
  2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self-diagnosis. Confirm that code No. 20 is displayed.
2. NG:
  1. Replace intake sensor.
  2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self-diagnosis. 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 M254 terminal 2 (R) and unified meter and A/C amp. harness connector M57 terminal 41 (P).
  1. 2 - 41 : Continuity should exist.
4. Check continuity between intake sensor harness connector M254 terminal 2 (R) and ground.
  1. 2 - Ground : Continuity should not exist.
Fig 4: Checking Intake Sensor-To-Unified Meter & A/C Amp. Circuit Continuity
Courtesy of NISSAN MOTOR CO., U.S.A.

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