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Test Dg: Knock Sensor: Testing

NOTE: For additional testing information, see DIAGNOSTIC AIDS .

NOTE: Freeze frame data will not be stored in the ECM for the knock sensor. The MIL will not light for a knock sensor malfunction.

1) DTC P0325: Check KS Circuit Continuity
DTC P0325 indicates an excessively high or low voltage is received by PCM from knock sensor. Possible causes for this fault are as follows:
- KS circuit open or shorted.
- Faulty knock sensor.
- Faulty PCM.
Turn ignition off. Disconnect PCM harness connector. Inspect connector for damaged pins and repair if necessary. Disconnect KS harness connector. Using DVOM, measure resistance of KS signal circuit (White wire) between PCM harness connector terminal No. 63 and KS harness connector. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in White wire. See WIRING DIAGRAMS article.

2) Check KS Circuit For Short To Ground

Using DVOM, measure resistance between GND and KS circuits at PCM harness connector. See PCM TERMINAL CIRCUIT IDENTIFICATION table. See Figure. If resistance is more than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short between affected circuits.

3) Check KS Circuit For Short To Power

Using DVOM, measure resistance between KS, VPWR and KAPWR circuits at PCM harness connector. See PCM TERMINAL CIRCUIT IDENTIFICATION table. See Figure. If all resistances are more than 10 k/ohms, go to next step. If any resistance measurement is 10 k/ohms or less, repair short between affected circuits. See WIRING DIAGRAMS article.

4) Check Resistance Of KS

Using DVOM, measure resistance between negative battery terminal and KS circuit at KS harness connector. If resistance is 500-620 k/ohms, replace PCM. If resistance is not 500-620 k/ohms, replace KS.