Diagnostic Procedure
- CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I
- Turn ignition switch "OFF".
- Disconnect ECM harness connector.
- Check resistance between ECM terminal 15 and engine ground.NOTE: It is necessary to use an ohmmeter which can measure more than 10 Mohm.
Courtesy of NISSAN MOTOR CO., U.S.A.
Resistance:
Approximately 500 - 620 kohm [at 25°C (77°F)]
- Also check harness for short to ground and short to power.
OK or NG
- OK: GO TO 5 .
- NG: GO TO 2.
- CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
- Disconnect knock sensor harness connector.
- Check harness continuity between ECM terminal 15 and knock sensor terminal 1. Refer to WIRING DIAGRAM
.
Continuity should exist.
- Also check harness for short to ground and short to power.
OK or NG
- OK: GO TO 4 .
- NG: GO TO 3.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F19, F116
- Harness for open or short between ECM and knock sensor
- Repair open circuit or short to ground or short to power in harness or connectors.
- CHECK KNOCK SENSOR
Check resistance between knock sensor terminal 1 and ground.
NOTE: It is necessary to use an ohmmeter which can measure more than 10 Mohm.Courtesy of NISSAN MOTOR CO., U.S.A.
Resistance: 500 - 620 kohm [at 25°C (77°F)]
CAUTION: Do not use any knock sensors that have been dropped or physically damaged. Use only new ones.OK or NG
- OK: GO TO 8 .
- NG: Replace knock sensor.
- RETIGHTEN GROUND SCREWS
Loose and retighten engine ground screws.
- GO TO 6.
- CHECK KNOCK SENSOR SHIELD CIRCUIT FOR OPEN AND SHORT
- Check harness continuity between knock sensor terminal 2 and engine ground. Refer to WIRING DIAGRAM
.
Continuity should exist.
- Also check harness for short to power.
OK or NG
- OK: GO TO 8 .
- NG: GO TO 7.
- Check harness continuity between knock sensor terminal 2 and engine ground. Refer to WIRING DIAGRAM
.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F19, F116
- Harness connectors F22, M33
- Harness for open between harness connector knock sensor and engine ground
- Repair open circuit or short to power in harness or connectors.
- CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT " .
- INSPECTION END