P0325

P0325-KNOCK SENSOR 1 CIRCUIT







- When Monitored:
Engine running.

- Set Condition:
The Knock Sensor circuit voltage falls below a minimum value at idle or deceleration. The minimum value is from a look-up table internal to the Powertrain Control Module (PCM) and is based on engine RPM. DTC will also set if the sensor voltage goes above 5.0 volts. One Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DTC
1. Ignition on, engine not running.
2. With a scan tool, read DTCs.

Is the DTC active at this time?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.

2. (K42) KNOCK SENSOR NO.1 SIGNAL SHORTED TO BATTERY VOLTAGE




1. Turn the ignition off.
2. Disconnect the No.1 Knock Sensor harness connector.
3. Disconnect the PCM harness connectors.
4. Ignition on, engine not running.
5. Measure the voltage on the (K42) Knock Sensor No.1 Signal circuit in the Knock Sensor harness connector.

Does the voltmeter indicate voltage present?

Yes

- Repair the short to battery voltage in the (K42) Knock Sensor No.1 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 3

3. (K42) KNOCK SENSOR NO.1 SIGNAL CIRCUIT OPEN




1. Turn the ignition off.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install PCM Pinout Box 8815 to perform diagnosis.

2. Measure the resistance of the (K42) Knock Sensor No.1 Signal circuit from the Knock Sensor harness connector to the appropriate terminal of the PCM Pinout Box 8815.

Is the resistance below 5.0 Ohms?

Yes

- Go To 4

No

- Repair the open in the (K42) Knock Sensor No.1 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

4. (K942) KNOCK SENSOR NO.1 RETURN CIRCUIT OPEN
1. Measure the resistance of the (K942) Knock Sensor No.1 Return circuit from the Knock Sensor harness connector to the appropriate terminal of PCM Pinout Box 8815.

Is the resistance below 5.0 Ohms?

Yes

- Go To 5

No

- Repair the open in the (K942) Knock Sensor No.1 Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. (K42) KNOCK SENSOR NO.1 SIGNAL SHORTED TO THE (K942) KNOCK SENSOR NO.1 RETURN CIRCUIT




1. Measure the resistance between the (K42) Knock Sensor No.1 Signal circuit and the (K942) Knock Sensor No.1 Return circuit in the Knock Sensor harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the short between the (K42) Knock Sensor No.1 Signal circuit and the (K942) Knock Sensor No.1 Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 6

6. (K42) KNOCK SENSOR NO.1 SIGNAL SHORTED TO GROUND




1. Measure the resistance between ground and the (K42) Knock Sensor No.1 Signal circuit in the Knock Sensor harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the short to ground in the (K42) Knock Sensor No.1 Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 7

7. KNOCK SENSOR
1. Replace the Knock Sensor.
2. Ignition on, engine not running.
3. With the scan tool, erase DTC.
4. Attempt to operate the vehicle using the information noted in the Freeze Frame.
5. With the scan tool, read DTCs.

Does the scan tool display the DTC that was previously erased?

Yes

- NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
- Replace and program the Powertrain Control Module (PCM).
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Test Complete.