Circuit Description
The knock sensors (KS) produce an AC signal under all engine operating conditions. The PCM calculates the average voltage range of each KS signal. If the KS system is operating normally, the PCM should monitor the KS voltage varying above and below a calculated average voltage. If the PCM detects a KS 1 signal voltage or a KS 2 voltage signal within the calculated average voltage range, a DTC will be set. A DTC P0327 refers to bank 1 knock sensor. A DTC P0332 refers to bank 2 knock sensor.
Conditions for Running the DTC
| • | DTCs P0101, P0102, P0103, P0117, P0118, P0121, P0122, P0123, P0125, P0336, P0341, P0502, P0503, P1114, P1115, or P1121 are not set. |
| • | The engine speed is between 1000-2500 RPM. |
| • | The throttle angle is more than 10 percent. |
| • | The engine load is more than 40 percent. |
| • | The engine coolant temperature (ECT) is more than 60°C (140°F). |
| • | The maximum spark retard is less than 15 degrees. |
| • | The system voltage is more than 9 volts. |
| • | The engine run time is more than 30 seconds. |
Conditions for Setting the DTC
The PCM detects a knock sensor 1 or a knock sensor 2 voltage within the calculated average voltage range.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics | ||||
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |
2 |
Important: If a mechanical engine knock can be heard, repair the engine mechanical problem before proceeding with this diagnostic. Refer to Symptoms - Engine Mechanical in Engine Mechanical.
Does the DTC fail this ignition? | -- | Go to Step 3 | Go to Intermittent Conditions |
3 |
Does the voltage measure near the specified value ? | 0 V | Go to Step 5 | Go to Step 4 |
4 | Repair the short to voltage in the KS signal circuit . Did you complete the repair ? | -- | Go to Step 9 | -- |
5 |
Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 6 |
6 |
Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 7 |
7 |
Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 8 |
8 | Replace the knock sensor. Refer to Knock Sensor 1 Replacement or Knock Sensor 2 Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
9 |
Does the DTC run and pass? | -- | Go to Step 10 | Go to Step 2 |
10 | With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK | |
