Diagnostic Procedure

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

CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check resistance between ECM terminal 15 and engine ground. Refer to WIRING DIAGRAM .
  NOTE: It is necessary to use an ohmmeter which can measure more than 10 MΩ.
  
  Resistance: Approximately 530 - 590kΩ [at 20°C (68°F)]
4. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 4.
2. NG: GO TO 2.
CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect ECM harness connector and knock sensor harness connector.
2. Check harness continuity between knock sensor terminal 1 and ECM terminal 15.
  Refer to WIRING DIAGRAM .
  
  Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 3.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  
  Fig 1: Identifying Knock Sensor
  Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK KNOCK SENSOR
Refer to COMPONENT INSPECTION .

OK or NG
1. OK: GO TO 4.
2. NG: Replace knock sensor.
RETIGHTEN GROUND SCREWS
Loosen and retighten engine ground screws.

Fig 2: Retightening Engine Ground Screws
Courtesy of NISSAN MOTOR CO., U.S.A.
1. GO TO 5.
CHECK KNOCK SENSOR SHIELD CIRCUIT FOR OPEN AND SHORT
1. Disconnect knock sensor harness connector.
2. Check harness continuity between knock sensor terminal 2 and ground. Refer to WIRING DIAGRAM .
  Continuity should exist.
3. Also check harness for short to power.
OK or NG
1. OK: GO TO 7.
2. NG: GO TO 6.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F26, M58
- Harness for open or short between knock sensor and ground
  1. Repair open circuit or short to power in harness connectors
CHECK INTERMITTENT INCIDENT
Perform TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .
1. INSPECTION END