P0327

2AR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0327,P0328: Knock Sensor 1 Circuit Low Input (Bank 1 or Single Sensor)


DESCRIPTION

Flat-type knock sensors (non-resonant type) have structures that can detect vibrations between approximately 6 kHz and 15 kHz.

Knock sensors are fitted onto the engine block to detect engine knocking.

The knock sensor contains a piezoelectric element which generates a voltage when it becomes deformed.

The voltage is generated when the engine block vibrates due to knocking. Any occurrence of engine knocking can be suppressed by delaying the ignition timing.





HINT
When DTC P0327 or P0328 is stored, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is delayed to its maximum retardation. Fail-safe mode continues until the ignition switch is turned off.

Reference: Inspection using an oscilloscope





The correct waveform is as shown.





MONITOR DESCRIPTION

If the output voltage transmitted by the knock sensor remains low or high for more than 1 second, the ECM interprets this as a malfunction in the sensor circuit, and stores a DTC.

The monitor for DTCs P0327 and P0328 begins to run when 5 seconds have elapsed since the engine was started.

If the malfunction is not repaired successfully, DTC P0327 or P0328 is stored 5 seconds after the engine is next started.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS

P0327: Knock Sensor Range Check (Low Voltage)





P0328: Knock Sensor Range Check (High Voltage)





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

2. Turn the ignition switch to ON and turn the Techstream on.

3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.

4. Turn the ignition switch off and wait for at least 30 seconds.

5. Turn the ignition switch to ON and turn the Techstream on [A].

6. Start the engine and wait 10 seconds.

7. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

8. Input the DTC: P0327 or P0328.

9. Check the DTC judgment result [B].





HINT
If the judgment result shows INCOMPLETE or UNKNOWN, idle the engine for 5 minutes and check the DTC judgment result again [C].

10. If the test result is UNKNOWN, enter the following menus: Powertrain / Engine / Trouble Codes / Pending.

11. Read Pending DTCs.

HINT
If a pending DTC is output, the system is malfunctioning.

12. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.

WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1. READ VALUE USING TECHSTREAM (KNOCK FEEDBACK VALUE)

(a) Connect the Techstream to the DLC3.

(b) Start the engine.

(c) Turn the Techstream on.

(d) Warm up the engine.

(e) Enter the following menus: Powertrain / Engine / All Data / Knock Feedback Value.

(f) Read the value while driving the vehicle.

OK:

The value changes.

HINT






The knock feedback value change can be confirmed by running the engine with a high load, for example, by activating the air conditioning system and racing the engine.

NG -- INSPECT ECM (KNK1 VOLTAGE)

OK -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems

2. INSPECT ECM (KNK1 VOLTAGE)

(a) Disconnect the knock sensor connector.





(b) Turn the ignition switch to ON.

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





(d) Reconnect the knock sensor connector.

NG -- CHECK HARNESS AND CONNECTOR (ECM - KNOCK SENSOR)
OK -- Continue to next step.

3. INSPECT KNOCK SENSOR

(a) Remove the knock sensor.





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





(c) Reinstall the knock sensor.

NG -- REPLACE KNOCK SENSOR Removal

OK -- REPLACE ECM Removal

4. CHECK HARNESS AND CONNECTOR (ECM - KNOCK SENSOR)

(a) Disconnect the knock sensor connector.

(b) Disconnect the ECM connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance (Check for Open):





Standard Resistance (Check for Short):





(d) Reconnect the knock sensor connector.

(e) Reconnect the ECM connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE ECM Removal