DTC 0304

COMPONENT DESCRIPTION
The knock sensor is attached to the cylinder block. it senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a voltage signal and sent to the ECM.






ECM TERMINALS AND REFERENCE VALUE
Specification data are reference values, and are measured between each terminal and (25) (ECCS ground).






ON BOARD DIAGNOSIS LOGIC
* Freeze frame data is not stored in the ECM for the knock sensor.
The MIL will not light for knock sensor malfunction. The knock sensor has one trip detection logic.


DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

CAUTION: Always drive vehicle at a safe speed.

NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch "OFF" and wait at least 5 seconds before conducting the next test.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10V.


Without Scan Tools
(1) Start engine and run it at least 5 seconds at idle speed.
(2) Turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
(3) Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.






Electrical Diagrams






Circuit Connectors






DIAGNOSTIC PROCEDURE






DIAGNOSTIC PROCEDURE


COMPONENT INSPECTION
Knock sensor






1. Disconnect knock sensor harness connector.
2. Check resistance between terminal (2) and ground. Approximately 500 - 620 k Ohms [at 25°C (77°F)]
- It is necessary to use an ohmmeter which can measure more than 10 M Ohms.

CAUTION: Do not use any knock sensors that have been dropped or physically damaged. Use a new one.