P0325

P0325-KNOCK SENSOR 1 CIRCUIT

Special Tools:










For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the engine run time greater than 30 seconds, engine speed greater than 2700 RPM, and engine coolant temperature greater than 0 C (32 F).

- Set Condition:
The Powertrain Control Module (PCM) detects that the Knock Sensor input voltage is:

above 4.0 volts

less than or equal to 1.0 volt with engine RPM at or above 2200

equal to 0.0 volts with engine RPM below 2200





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

Diagnostic Test

1. ACTIVE DTC
1. Start the engine and allow it to reach normal operating temperature.

WARNING:
When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to reset.

2. Raise the engine speed to 2700 RPM for a minimum of 30 seconds.
3. With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

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

2. CHECK THE (K42) KS SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the Knock Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (K42) KS Signal circuit in the Knock Sensor harness connector.

Is the voltage above 5.2 volts?

Yes

- Repair the (K42) KS Signal circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 3

3. CHECK THE (K42) KS SIGNAL CIRCUIT FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance between ground and the (K42) KS Signal circuit in the Knock Sensor harness connector.

Is the resistance above 10k Ohms?

Yes

- Go To 4

No

- Repair the (K42) KS Signal circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

4. CHECK FOR THE (K42) KS SIGNAL CIRCUIT SHORTED TO THE (K942) KS RETURN CIRCUIT




1. Measure the resistance between the (K42) KS Signal circuit and the (K942) KS Return circuit in the Knock Sensor harness connector.

Is the resistance above 10k Ohms?

Yes

- Go To 5

No

- Repair the (K42) KS Signal circuit for a short to the (K942) KS Return circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

5. CHECK THE (K42) KS SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE

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 the GPEC Diagnostic Adaptor to perform the diagnosis.

1. Connect the (10436).
2. Measure the resistance of the (K42) KS Signal circuit between the Knock Sensor harness connector and the GPEC Adaptor.

Is the resistance below 5.0 Ohms?

Yes

- Go To 6

No

- Repair the (K42) KS Signal circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

6. CHECK THE (K942) KS RETURN CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K942) KS Return circuit between the Knock Sensor harness connector and the GPEC Adaptor.

Is the resistance below 5.0 Ohms?

Yes

- Go To 7

No

- Repair the (K942) KS Return for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

7. KNOCK SENSOR
1. Turn the ignition off.
2. Connect the PCM C2 harness connector.
3. Replace the Knock Sensor.
4. Start the engine and allow it to reach normal operating temperature.
5. With the scan tool, select View DTCs.

Is status Active for this DTC?

Yes

- Go To 8

No

- Test Complete.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

8. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Knock Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.