For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC P0324: Knock Sensor (KS) Module Performance
DTC P0325: Knock Sensor (KS) Circuit Bank 1
DTC P0326: Knock Sensor (KS) Performance
DTC P0327: Knock Sensor (KS) Circuit Low Voltage Bank 1
DTC P0328: Knock Sensor (KS) Circuit High Voltage Bank 1
DTC P0330: Knock Sensor (KS) Circuit Bank 2
DTC P0332: Knock Sensor (KS) Circuit Low Voltage Bank 2
DTC P0333: Knock Sensor (KS) Circuit High Voltage Bank 2

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Knock Sensor Signal | P0327, P0328, P0332, P0333 | P0325, P0330 | P0327, P0328, P0332, P0333 | P0326

### Circuit Description

The knock sensor (KS) system enables the control module to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The engine control module (ECM) monitors 2 separate KS, located under the intake manifold. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The control module receives the KS signal through 2 isolated signal circuits. The control module adjusts the spark timing based on the amplitude and the frequency of the KS signal.

### Conditions for Running the DTC

#### P0324

DTC P0324 runs continuously when the engine speed is greater than 2,000 RPM and engine load is greater than a calibrated amount.

#### P0326

DTC P0326 runs continuously when:

• | The engine speed is greater than or equal to 1,200 RPM.

• | The MAP is greater than 80 kPa.

• | DTC P0120, P0121, P0122 or P0123 are not set.

• | Express Spark Retard Turn.

#### P0325, P0330, P0327, P0328, P0332, P0333

DTC P0325, P0330, P0327, P0328, P0332, P0333 runs continuously when:

• | The engine coolant temperature (ECT) sensor is more than 75°C (167°F).

• | The engine running time is greater than 90 seconds.

### Conditions for Setting the DTC

#### P0324

• | The control module has detected an internal circuitry fault.

• | It occurs 50 times during the 100 tests.

#### P0325 and P0330

• | The KS signal circuits are open or short to each other.

• | It occurs 50 times during the 100 tests.

#### P0326

• | The ECM detects that KS system is excessive activity due to engine components excessive noise such as loose bracket, noisy lifter.

• | It occurs 50 times during the 100 tests.

#### P0327, P0328, P0332, and P0333

The KS signal circuits are shorted to voltage or ground.

### Action Taken When the DTC Sets

• | DTCs P0324, P0325, P0326, P0327, P0328, P0330, P0332, P0333 are Type B DTCs.

• | Spark timing will be retarded to reduce spark knock, and may cause reduced engine power.

### Conditions for Clearing the DTC

DTCs P0324, P0325, P0326, P0327, P0328, P0330, P0332, P0333 are Type B DTCs.

### Diagnostic Aids

• | Inspect the KS for physical damage. A KS that is dropped or damaged may cause a DTC to set.

• | Inspect the KS for proper installation. A KS that is loose or over torqued may cause a DTC to set.

• | The KS mounting surface should be free of burrs, casting flash, and foreign material.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

• | Scan Tool Data List

• | Scan Tool Data Definitions

• | Engine Control Module Scan Tool Information

### Circuit/System Testing

Note: If DTC P0325, P0327, P0328, P0330, P0332, or P0333 are set, diagnose those DTCs first.

#### P0324

This DTC indicates an internal control module circuitry failure. Replace the ECM.

#### P0325, P0327, P0328, P0330, P0332, and P0333

1. Turn the ignition to ON without the engine running.
2. Disconnect the rear engine C104.
3. Measure for 2-3 volts between each of the following circuits and ground on the ECM side of the harness connector:

• | Knock Sensor Bank 1 signal circuit terminal G

• | Knock Sensor Bank 1 signal circuit terminal H

• | Knock Sensor Bank 2 signal circuit terminal J

• | Knock Sensor Bank 2 signal circuit terminal K

⇒ | If less than the specified range, test the circuits for a short to ground, or an open/high resistance. If the circuit test normal, replace the ECM.

⇒ | If greater than the specified range, test the circuits for a short to voltage. If the circuit test normal, replace the ECM.

4. Test the KS circuits on the KS side of the connector for the following:

• | Open/High Resistance

• | Short to Ground

• | Short to any other circuit

5. If all circuits test normal, replace the appropriate KS.

#### P0326

| Note: If DTC P0325, P0327, P0328, P0330, P0332, P0333, P0335 or P0336 are set, diagnose those DTCs first.

• | Inspect for a loose or broken vehicle accessory or accessory bracket.

• | Inspect for excessive engine mechanical noise.

### Component Testing

1. Knock Sensor 1: Connect the DMM between the KS signal terminal G and H on the sensor side of the KS inline harness connector C104.

OR

2. Knock Sensor 2: Connect the DMM between the KS signal terminal J and K on the sensor side of the KS inline harness connector C104.
3. Set the DMM within the 400 mV, and wait for the DMM to stabilize at about 0 volt.

Note: DO NOT tap on plastic engine components.

4. Tap on the engine block with a non-metallic object near the KS while observing the signal indicated on the DMM.
5. The DMM should display a fluctuating frequency while tapping on the engine block.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Knock Sensor 1 Replacement

• | Knock Sensor 2 Replacement

• | Control Module References for ECM replacement, setup, and programming