Diagnostic Procedure For Intake Sensor

SYMPTOM: Intake sensor circuit is open or shorted. (56 or 57 is indicated on front air control display as a result of conducting Self-diagnosis.)

Fig 1: Intake Sensor Circuit Diagram

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

1. 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 M146 terminal 2 and ground.

      2 - Ground: Approx. 5V 

   Fig 2: Checking Voltage Between Intake Sensor Harness Connector M146 Terminal 2 And Ground

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

   OK or NG 

   OK: GO TO 2.

   NG: GO TO  4.

2. CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND FRONT AIR CONTROL 
   1. Turn ignition switch OFF.
   2. Disconnect front air control connector.
   3. Check continuity between intake sensor harness connector M146 terminal 1 and front air control harness connector M49 terminal 13.

      1 - 13: Continuity should exist. 

   Fig 3: Checking Continuity Between Intake Sensor And Front Air Control Connector Terminals

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

   OK or NG 

   OK: GO TO 3.

   NG: Repair harness or connector.

3. CHECK INTAKE SENSOR 

   Refer to "INTAKE SENSOR ".

   OK or NG 

   OK :

   1. Replace front air control. Refer to "FRONT AIR CONTROL ".
   2. Go to "A/C SYSTEM SELF-DIAGNOSIS FUNCTION " and perform self-diagnosis.

   NG :

   1. Replace intake sensor. Refer to "INTAKE SENSOR ".
   2. Go to "A/C SYSTEM SELF-DIAGNOSIS FUNCTION " and perform self-diagnosis.
4. CHECK CIRCUIT CONTINUITY BETWEEN INTAKE SENSOR AND FRONT AIR CONTROL 
   1. Turn ignition switch OFF.
   2. Disconnect front air control connector.
   3. Check continuity between intake sensor harness connector M146 terminal 2 and front air control harness connector M49 terminal 12.

      2 - 12: Continuity should exist. 

      Fig 4: Checking Continuity Between Harness Connector M146 Terminal 2 And Connector M49 Terminal 12

      Courtesy of NISSAN MOTOR CO., U.S.A.
   4. Check continuity between intake sensor harness connector M146 terminal 2 and ground.

      2 - Ground: Continuity should not exist. 

   OK or NG 

   OK :

   1. Replace front air control. Refer to "FRONT AIR CONTROL ".
   2. Go to "A/C SYSTEM SELF-DIAGNOSIS FUNCTION " and perform self-diagnosis.

   NG: Repair harness or connector.