Diagnostic Procedure
WARNING: This page is about a different car, the 2005 Infiniti G35. 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
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check resistance between ECM terminal 15 and ground. Refer to Wiring Diagram.NOTE: It is necessary to use an ohmmeter which can measure more than 10 MΩ.
Resistance: Approximately 532 - 588 kΩ [at 20°C (68°F)]
- Also check harness for short to ground and short to power.
OK or NG
- OK: GO TO 4.
- 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 F37, F229
- 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
Refer to "Component Inspection ".
OK or NG
- OK: GO TO 5.
- NG: Replace knock sensor.
- CHECK GROUND CONNECTIONS
Loosen and retighten two ground screws on the body. Refer to "Ground Inspection ".
OK or NG
- OK: GO TO 6.
- NG: Repair or replace ground connections.
- CHECK KNOCK SENSOR SHIELD CIRCUIT FOR OPEN AND SHORT
- Disconnect knock sensor harness connector.
- Check harness continuity between knock sensor terminal 2 and ground. Refer to Wiring Diagram.
Continuity should exist.
OK or NG
- OK: GO TO 8.
- NG: GO TO 7.
- DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors F37, F229
- Harness connectors F102, M72
- Harness for open or short between knock sensor terminal 2 and ground
- : Repair open circuit or short power in harness or connectors.
- CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".
- : INSPECTION END