Troubleshooting

DTC P0325 KNOCK SENSOR 1 CIRCUIT (BANK 1 OR SINGLE SENSOR)

CIRCUIT DESCRIPTION

DTC Detection Condition:

The flat type engine knock sensor (non-resonant type) has a structure that can detect vibration in a wide frequency range, from about 6 kHz to 15 kHz.

The sensor, located on the cylinder block, detects spark knock. When "spark knock" occurs, the knock sensor picks-up vibrations in a specific frequency range. When the ECM detects signal voltage in this frequency range, it retards the ignition timing to suppress the knocking. The ECM also senses background engine noise with the knock sensor and uses this noise to check for faults in the sensor.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

If the output signal remains low or high for more than 10 seconds, the ECM interprets this as a fault in the knock sensor and sets a DTC.

Wiring Diagram:

Step 1:

Step 2 - 3:

Step 4 - 5:

Step 6:

INSPECTION PROCEDURE

HINT:
- DTC P0325, P0327 and P0328 are for the bank 1 knock sensor circuit.
- DTC P0330, P0332 and P0333 are for the bank 2 knock sensor circuit.
- Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

CHECK FOR INTERMITTENT PROBLEMS

Hand-held tester only:
By putting the vehicle's ECM in the check mode, the 1 trip detection logic is possible instead of the 2 trip detection logic, and the sensitivity to detect faults is increased. This makes it easier to detect intermittent problems.

a. Clear the DTCs.
b. Set the check mode.
c. Perform a simulation test.
d. Check the connector and terminal.
e. Wiggle the harness and the connector.