P0328

2AZ-FXE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0327: Knock Sensor 1 Circuit Low Input (Bank 1 or Single Sensor)

DTC P0327 - Knock Sensor 1 Circuit Low Input (Bank 1 or Single Sensor)

DTC P0328 - Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor)

DESCRIPTION

Flat type knock sensors (non-resonant type) have a structure that can detect vibrations over a wide band of frequencies: between approximately 6 kHz and 15 kHz.
The knock sensor is 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. Occurrence of engine knocking can be suppressed by delaying the ignition timing.

HINT: When any of DTCs P0327 and P0328 are set, the ECM (included in the hybrid vehicle control ECU) enters fail-safe mode. During fail-safe mode, the ignition timing is delayed to its maximum retardation. Fail-safe mode continues until the power 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 (included in the hybrid vehicle control ECU) interprets this as a malfunction in the sensor circuit, and sets 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, either DTC P0327 or P0328 is set 5 seconds after the engine is next started.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

Knock Sensor Range Check (Low voltage) P0327:

Knock Sensor Range Check (High voltage) P0328:

WIRING DIAGRAM

INSPECTION PROCEDURE
HINT: Read freeze frame data using Techstream. The ECM (included in the hybrid vehicle control ECU) records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

1. READ VALUE USING TECHSTREAM (KNOCK FB VAL)
(a) Connect Techstream to the DLC3.
(b) Put the engine in inspection mode Inspection Mode Procedure.
(c) Turn the tester on.
(d) Warm up the engine.
(e) Select the following menu items: Powertrain / Engine / Data List / Knock Feedback Value.
(f) Read the values displayed on the tester while driving the vehicle.
Standard:
The values change.

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 revving up the engine.

NG -- CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - KNOCK SENSOR)
OK -- CHECK FOR INTERMITTENT PROBLEMS
2. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - KNOCK SENSOR)

(a) Disconnect the C64 hybrid vehicle control ECU connector.
(b) Measure the resistance between the terminals.
Standard resistance:

(c) Reconnect the hybrid vehicle control ECU connector.
NG -- INSPECT KNOCK SENSOR
OK -- Continue to next step.
3. INSPECT HYBRID VEHICLE CONTROL ECU (KNK1 VOLTAGE)

(a) Disconnect the C30 knock sensor connector.
(b) Turn the power switch on (IG).
(c) Measure the voltage between the knock sensor terminals.
Standard voltage:

(d) Reconnect the knock sensor connector.
NOTE: The fault may be intermittent. Check the wire harness and connectors carefully and retest.

NG -- REPLACE HYBRID VEHICLE CONTROL ECU
OK -- CHECK FOR INTERMITTENT PROBLEMS
4. INSPECT KNOCK SENSOR

(a) Remove the knock sensor.
(b) Measure the resistance between the terminals.
Standard resistance: