Diagnostic Procedure For Ambient Sensor

WARNING: This page is about a different car, the 2004 Infiniti M45. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM: Ambient sensor circuit is open or shorted. (21 or -21 is indicated on auto amp. As a result of conducting Self-diagnosis STEP-2).

Fig 1: Identifying Ambient Sensor Circuit

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

CHECK VOLTAGE BETWEEN AMBIENT SENSOR AND GROUND
1. Disconnect ambient sensor connector.
2. Turn ignition switch ON.
3. Check voltage between ambient sensor harness connector E58 terminal 1 (G/W) and ground.
  
  Fig 2: Checking Ambient Sensor-To-Ground Voltage
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  1 - Ground: Approx. 5V
OK or NG
1. OK: GO TO 2.
2. NG: GO TO 4.
CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT SENSOR AND AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect auto amp. connector.
3. Check continuity between ambient sensor harness connector E58 terminal 2 (R/Y) and auto amp. harness connector M119 terminal 11 (R/Y).
  
  Fig 3: Checking Ambient Sensor-To-Auto Amp. Continuity
  Courtesy of NISSAN MOTOR CO., U.S.A.
2-11 continuity should exist.

OK or NG
1. OK: GO TO 3.
2. NG: Repair harness or connector.
CHECK AMBIENT SENSOR
Refer to AMBIENT SENSOR .

OK or NG
1. OK:
  1. Replace auto amp.
  2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self diagnosis STEP-2. Confirm that code No. 20 is displayed.
2. NG:
  1. Replace ambient 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 AMBIENT SENSOR AND AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect auto amp. harness connector.
3. Check continuity between ambient sensor harness connector E58 terminal 1 (G/W) and auto amp. harness connector M119 terminal 2 (G/W).
  
  Fig 4: Checking Ambient Sensor-To-Auto Amp. Continuity
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  1-2: continuity should exist.
4. Check continuity between auto amp. harness connector M119 terminal 2 (G/R) and ground.
  2-Ground: continuity should exist.
OK or NG
1. OK:
  1. Replace auto amp.
  2. Go to self-diagnosis FUNCTION CONFIRMATION PROCEDURE and perform self-diagnosis STEP-2.Confirm that code no. 20 is displayed.
2. NG: Repair harness or connector.