Toyota Tundra. Manual — part 1556

HINT:

When any of DTCs P0327, P0328, P0332, P0333, P032C, P032D, P033C and P033D are 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

Fig. 129: Identifying KNK1 Signal Waveform
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Standard

WAVEFORM REFERENCE

Tester Connection

Tool Setting

Condition

Specified Condition

D74-94 (KNK1) - D74-93

0.01 to 10
V/DIV.

Keep engine speed at 4000 RPM The correct waveform is

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

MONITOR DESCRIPTION

The knock sensor, located on the cylinder block, detects spark knock. When spark knock occurs, the
piezoelectric element of the sensor vibrates. When the ECM detects a voltage in this frequency range, it retards
the ignition timing to suppress the spark knock.

The ECM also senses background engine noise with the knock sensor and uses this noise to check for faults in
the sensor. If the knock sensor output voltage is outside the normal range, the ECM interprets this as a fault in
the knock sensor and stores a DTC.

MONITOR STRATEGY

MONITOR STRATEGY

(EKNK)

0.01 to 10
msec./DIV.

with warm engine

as shown

D74-117 (KNK2) - D74-
116 (EKN2)

0.01 to 10
V/DIV.
0.01 to 10
msec./DIV.

Keep engine speed at 4000 RPM
with warm engine

The correct waveform is
as shown

D74-96 (KNK3) - D74-95
(EKN3)

0.01 to 10
V/DIV.
0.01 to 10
msec./DIV.

Keep engine speed at 4000 RPM
with warm engine

The correct waveform is
as shown

D74-119 (KNK4) - D74-
118 (EKN4)

0.01 to 10
V/DIV.
0.01 to 10
msec./DIV.

Keep engine speed at 4000 RPM
with warm engine

The correct waveform is
as shown

Related DTCs

P0327: Knock sensor (for Bank 1 Sensor 1) open/short (Low
voltage)
P0328: Knock sensor (for Bank 1 Sensor 1) open/short (High
voltage)
P0332: Knock sensor (for Bank 2 Sensor 1) open/short (Low
voltage)
P0333: Knock sensor (for Bank 2 Sensor 1) open/short (High
voltage)
P032C: Knock sensor (for Bank 1 Sensor 2) open/short (Low
voltage)
P032D: Knock sensor (for Bank 1 Sensor 2) open/short (High
voltage)
P033C: Knock sensor (for Bank 2 Sensor 2) open/short (Low
voltage)
P033D: Knock sensor (for Bank 2 Sensor 2) open/short (High
voltage)

Required Sensors/Components (Main) Knock sensor (Bank 1, 2 Sensor 1, 2)
Required Sensors/Components
(Related)

-

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

TYPICAL ENABLING CONDITIONS

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

Knock Sensor Range Check (Low voltage): P0327, P0332, P032C and P033C:

TYPICAL MALFUNCTION THRESHOLDS - KNOCK SENSOR (LOW VOLTAGE)

Knock Sensor Range Check (High voltage): P0328, P0333, P032D and P033D:

TYPICAL MALFUNCTION THRESHOLDS - KNOCK SENSOR RANGE CHECK (HIGH
VOLTAGE)

WIRING DIAGRAM

Frequency of Operation

Continuous

Duration

1 second

MIL Operation

Immediate

Sequence of Operation

None

Monitor runs whenever following DTCs are not present

None

Battery voltage

10.5 V or more

Time after engine start

5 seconds or more

Knock sensor voltage

Less than 0.5V

Knock sensor voltage

More than 4.5 V

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra

Fig. 130: Knock Sensor - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE

HINT:



DTCs P0327 and P0328 are for the bank 1 sensor 1 knock sensor circuit.



DTCs P032C and P032D are for the bank 1 sensor 2 knock sensor circuit.



DTCs P0332 and P0333 are for the bank 2 sensor 1 knock sensor circuit.



DTCs P033C and P033D are for the bank 2 sensor 2 knock sensor circuit.



Read freeze frame data using the Techstream. Freeze frame data records the engine condition when
malfunctions are detected. 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.

1. INSPECT KNOCK SENSOR

a. Disconnect the D74 ECM connector.

2009 Toyota Tundra

2009 ENGINE PERFORMANCE Engine Control System (3UR-FBE) - Tundra