Lexus RX300 (MCU15). Service manual — part 208

A00304

Knock Sensor

Engine ECU

EA1

Male
Connector

Female
Connector

1

1

1 1

2 2

KNKR

KNKL

EA1

FI7050
S06024
S06025

DI–64

–

DIAGNOSTICS

ENGINE

LEXUS RX300 (RM785E)

INSPECTION PROCEDURE

HINT:

S

DTC P0325 is for the right bank knock sensor circuit.

S

DTC P0330 is for the left bank knock sensor circuit.

S

Read freeze frame data using hand–held tester or OBD scan tool. Because freeze frame records the
engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining
whether the vehicle was running or stopped, the engine was warmed up or not, the air–fuel ratio was
lean or rich, etc. at the time of the malfunction.

1

Connect OBD scan tool or hand–held tester, and check knock sensor circuit.

PREPARATION:
(a)

Connect the OBD scan tool or hand–held tester to the
DLC3.

(b)

Disconnect the wire to wire connector EA1.

(c)

Connect the terminals of the disconnected EA1 male con-
nector and EA1 female as follows.

Male connector ↔ Female connector

Terminal 1 ↔ Terminal 2

Terminal 2 ↔ Terminal 1

(d)

Turn the ignition switch ON and push the OBD scan tool
or hand–held tester main switch ON.

(e)

After the engine is warmed up, perform quick racing to
4,000 rpm three times.

CHECK:
Check the DTC.
RESULT:

Type I

DTC same as when vehicle brought in

P0325 → P0325 or P0330 → P0330

Type II

DTC different to when vehicle brought in

P0325 → P0330 or P0330 → P0325

FI6510

FI6607

A00113

KNK Signal Waveform

0.5 V
/Division

5 msec./Division

100 µsec./Division

0V

200 mV
/Division

0V

–

DIAGNOSTICS

ENGINE

DI–65

LEXUS RX300 (RM785E)

Reference: INSPECTION USING OSCILLOSCOPE

S

With the engine racing (4,000 rpm), check the waveform
between terminals KNKR, KNKL of the ECM connector
and body ground.

HINT:
The correct waveform is as shown.

S

Spread the time on the horizontal axis, and confirm that
period of the wave is 141 µsec. (Normal mode vibration
frequency of knock sensor: 7.1 kHz)

HINT:
If normal mode vibration frequency is not 7.1 kHz, the sensor
is malfunctioning.

Type II

Go to step 3.

Type I

2

Check for open and short in harness and connector between EA1 connector and
engine ECU (See page IN–32).

NG

Repair or replace harness or connector.

OK

Check and replace engine ECU
(See page IN–32).

DI–66

–

DIAGNOSTICS

ENGINE

LEXUS RX300 (RM785E)

3

Check for open and short in harness and connector between EA1 connector and
knock sensor (See page IN–32).

ȡ

HINT:

S

If DTC P0325 has changed to P0330, check the knock sensor circuit on the right bank side.

S

If DTC P0330 has changed to P0325, check the knock sensor circuit on the left bank side.

NG

Repair or replace harness or connector.

OK

Replace knock sensor.

A06159

10

E8

Engine ECU

O

Crankshaft Position Sensor

Right Bank VVT Sensor (Camshaft Position Sensor)

NE+

B–W

E2

VV1

NE–

VV2

1

16

E7

24

E7

22

E7

2

W

B

W

L

1

2

1

2

Left Bank VVT Sensor (Camshaft Position Sensor)

W

–

DIAGNOSTICS

ENGINE

DI–67

LEXUS RX300 (RM785E)

DTC

P0335

Camshaft Position Sensor Circuit
Malfunction

CIRCUIT DESCRIPTION

Crankshaft position sensor (NE signal) consist of a signal plate and pick up coil.
The NE signal plate has 34 teeth and is mounted on the crankshaft. The NE signal sensor generates 34
signals of every engine revolution. The engine ECU detects the standard crankshaft angle based on the G2
signals, and the actual crankshaft angle the engine speed by the NE signals.

DTC No.

DTC Detecting Condition

Trouble Area

No crankshaft position sensor signal to engine ECU during

S Open or short in crankshaft position sensor circuit

No crankshaft position sensor signal to engine ECU during

ki

S O en or short in crankshaft osition sensor circuit

S Crankshaft position sensor

P0335

cranking

S Crankshaft position sensor

S Starter

Open in NE– circuit

S Starter

S Engine ECU

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

S

Read freed frame data using hand–held tester. Because freeze frame records the engine conditions
when the malfunction is detected, when troubleshooting it is useful for determining whether the vehicle
was running or stopped, the engine warmed up or not, the air–fuel ratio lean or rich, etc. at the time
of the malfunction.

S

Perform troubleshooting of DTC P0335 first. If no trouble is found, troubleshoot the following mechani-
cal system.

DI4EB–14