• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Knock Sensor 1 Signal | P0327, P0328 | P0327 | P0328 | P0326 |
Knock Sensor 2 Signal | P0332, P0333 | P0332 | P0333 | P0331 |
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 KS is located on the intake side of the engine block. The KS produces an AC voltage signal that varies depending on the vibration level during engine operation. The ECM receives the KS signal through 2 isolated signal circuits. The ECM adjusts the spark timing based on the amplitude and the frequency of the KS signal.
This DTC runs continuously when:
• | The engine speed is greater than 1,600 RPM. |
• | The engine load is greater than a calibrated amount. |
• | DTCs P0326 or P0331 are not set. |
These DTCs run continuously when:
• | The engine is running |
• | DTCs P0120, P0121, P0122, or P0123 are not set |
These DTCs run continuously when:
• | The engine coolant temperature (ECT) is greater than -40°C (-40°F) |
• | The engine run time is greater than 1 second. |
The ECM has detected an internal circuitry fault.
• | The KS signal indicates an excessive engine knock is present. |
• | The ECM commanded spark retard at a given engine load and speed is more than the calibrated value. |
• | The above conditions exist for up to 6 seconds. |
The KS signal circuits are shorted to ground or power.
DTCs P0324, P0326, P0327, P0328, P0331, P0332, and P0333 are Type B DTCs.
DTCs P0324, P0326, P0327, P0328, P0331, P0332, and P0333 are Type B DTCs.
• | 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 should be free of thread sealant. |
• | The KS mounting surface should be free of burrs, casting flash, and foreign material. |
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
• | If P0327, P0328, P0332, or P0333 are also set, preform those diagnostics first. |
• | This DTC indicates an internal ECM circuitry failure. Replace the K20 ECM. |
Note: If the KS lead is damaged in any way, replace the KS.
• | 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. |
Note: If DTC P0335 or P0336 are also set, diagnose those DTCs first. |
• | Inspect for a loose or broken vehicle accessory or accessory bracket. |
• | Inspect for excessive engine mechanical noise. |
Note: DO NOT tap on plastic engine components.
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for ECM replacement, setup, and programming |