P0332
DTC P0324, P0325, P0326, P0327, P0328, P0330, P0332, or P0333
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0324
- Knock Sensor Module Performance
DTC P0325
- Knock Sensor Circuit Bank 1
DTC P0326
- Knock Sensor Performance
DTC P0327
- Knock Sensor Circuit Low Voltage Bank 1
DTC P0328
- Knock Sensor Circuit High Voltage Bank 1
DTC P0330
- Knock Sensor Circuit Bank 2
DTC P0332
- Knock Sensor Circuit Low Voltage Bank 2
DTC P0333
- Knock Sensor Circuit High Voltage Bank 2
Diagnostic Fault Information
Circuit/System Description
The knock sensor (KS) system enables the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The ECM monitors 2 separate KS, one on each side of the engine block. Each KS produces an AC voltage that varies, depending on the vibration levels detected during engine operation. The ECM receives the KS signal through 2 isolated signal circuits for each KS. The ECM adjusts the spark timing based on the amplitude and frequency of each KS signal. The ECM learns a minimum noise level for each sensor at idle speeds, and uses calibrated noise level values for the rest of the RPM range. The ECM should monitor a normal KS signal within the noise channel.
Conditions for Running the DTC
P0324
* DTC P0325, P0326, P0327, P0328, P0330, P0332, or P0333 are not set.
* The engine speed is at least 400 RPM.
* DTC P0324 runs continuously when the above conditions are met.
P0325 and P0330
* DTC P0324, P0325, P0326, P0327, P0328, P0330, P0332, or P0333 are not set.
* The engine speed is at least 400 RPM.
* The engine coolant temperature (ECT) is warmer than -40°C (-40°F).
* The engine run time is at least 2 s.
* DTCs P0325 and P0330 run continuously when the above conditions are met.
P0326
* DTC P0068, P0606, P1516, P2101, P2135, or P2176 are not set.
* The engine speed is at least 400 RPM.
* The MAP is at least 10 kPa.
* DTC P0324 runs continuously when the above conditions are met.
P0327, P0328, P0332, and P0333
* The engine coolant temperature (ECT) is warmer than -40°C (-40°F).
* The engine run time is at least 2 s.
* DTCs P0327, P0328, P0332, and P0333 run continuously when the above conditions are met.
Conditions for Setting the DTC
P0324
The ECM has detected an internal circuitry fault.
P0325 or P0330
The knock sensor signal circuits are open or shorted together for 5 s.
P0326
* The knock sensor signal indicates an engine knock is present.
* The ECM has commanded the spark retard to a value which is more than the calibrated valve, for a specific engine load and speed.
* The above conditions exist for more than 5 s.
P0327, P0328, P0332, and P0333
The knock sensor signal circuits are shorted to voltage or ground.
Action Taken When the DTC Sets
* DTCs P0324, P0325, P0326, P0327, P0328, P0330, P0332, and P0333 are Type B codes.
* The ignition timing is retarded to reduce the potential of engine damaging spark knock.
Conditions for Clearing the DTC
DTCs P0324, P0325, P0326, P0327, P0328, P0330, P0332, and P0333 are Type B codes.
Diagnostic Aids
* Inspect the knock sensor for physical damage. A knock sensor that is dropped or damaged may cause a DTC to set.
* Inspect the knock sensor for proper installation. A knock sensor that is loose or over-torqued may cause a DTC to set.
* The knock sensor mounting surface should be free of burs, casting flash, and foreign material.
* The KS must be clear of hoses, brackets, and engine electrical wiring.
Reference Information
Schematic Reference
Engine Controls Schematics ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Electronic Ignition System Description (Electronic Ignition System Description)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
* J 35616 GM Approved Terminal Test Kit
* For equivalent regional tools, refer to Special Tools (Tools and Equipment).
Circuit/System Verification
1. Engine at operating temperature, observe DTC information with a scan tool. DTC P0324, P0325, P0326, P0327, P0328, P0330, P0332, or P0333 should not set.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Note:
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using these diagnostic procedures.
* If an engine mechanical noise can be heard, repair the condition before proceeding with this diagnostic. Refer to Symptoms - Engine Mechanical (Symptoms - Engine Mechanical).
P0324
Note: If DTC P0325, P0326, P0327, P0328, P0330, P0332, or P0333 are also set, diagnose those DTCs first.
DTC P0324 indicates an internal control module circuitry failure. Replace the ECM.
P0325, P0326, P0327, P0328, P0330, P0332, P0333
1. Ignition OFF, disconnect the affected B68 KS.
2. Ignition OFF. Connect a DMM to both KS signal circuits, terminals A and B, at the affected B68 KS. Set the DMM to the 400 mV AC scale, select the Hz mode. Let the reading stabilize at 0 Hz.
Note: DO NOT tap on plastic engine components.
3. Tap on the engine block with a non-metallic object near the affected B68 KS and observe the DMM for a fluctuating frequency.
• If the DMM does not display a fluctuating frequency while tapping on the engine block then replace the affected B68 KS.
4. Verify the affected B68 KS is properly tightened, refer to Fastener Tightening Specifications (Fastener Tightening Specifications).
5. Ignition OFF, with appropriate length jumper wires, connect the KS1 harness to the B68 KS2 sensor and the KS2 harness to the B68 KS1 sensor.
6. Monitor the DTCs using a scan tool. Operate the vehicle within the conditions for running the DTC. Verify the fault does not follow the sensor in question.
• If the fault follows the sensor in question, replace the appropriate B68 KS.
7. Ignition OFF, remove the jumper wires from the previous step.
8. Measure for 2-3 volts between each of the following circuits and ground on the ECM side of the harness connector:
* The B68 KS signal circuit, terminal A
* The B68 KS signal circuit, terminal B
• If less than the specified range, test the circuits for a short to ground or an open/high resistance. If the circuits test normal, replace the K20 ECM.
• If greater than the specified range, test the circuits for a short to voltage. If the circuits test normal, replace the K20 ECM.
9. Test for intermittent or poor connections at the K20 ECM, B68 KS, and in-line connectors where present.
10. If all circuits test normal, replace the K20 ECM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Engine Control Module Programming and Setup (Testing and Inspection)
* Engine Control Module Replacement (Service and Repair)
* Knock Sensor Replacement (Service and Repair)