Lexus ES300 (2002 year). Service manual — part 366

A53763

NE-

VV2+

VV2-

VV1+

GND

CH1

GND

CH2

A61582

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-83

236

2002 LEXUS ES300 REPAIR MANUAL (RM911U)

DTC

P0340

CAMSHAFT POSITON SENSOR CIRCUIT
MALFUNCTION

CIRCUIT DESCRIPTION

The camshaft position sensor (VV1 signal) consists of a signal plate and a pick up coil. On the signal plate
for a cam position sensor, there are three convex on its outer circumference and it is fixed to the camshaft
timing gear.
When the camshaft turns, the convex of the signal plate and the air-gap over the pick up coil will switch, and
with this the magnetic field will change and generate electricity inside the pick up coil. In addition, VV2 signal
adopts a sensor using a signal plate and a magnetic resistance element. By switching the air-gap of the
signal plate and the sensor, ECM voltage will be converted to a rectangular move and output as a signal.
The NE signal plate has 34 teeth and is mounted on the crankshaft. The NE signal sensor generates 34
signals at every engine revolution. The ECM detects the crankshaft angle based on the G signal and the
actual crankshaft angel and the engine speed by the NE signal.

DTC No.

DTC Detecting Condition

Trouble Area

P0340

No crank position sensor No.1 signal to ECM during cranking
(2 trip detection logic)

Open or short in camshaft position sensor circuit

Crank position sensor No.1

P0340

No crank position sensor No.1 signal to ECM with engine
speed 600 rpm or more

Crank osition sensor No.1

Camshaft timing gear

ECM

WIRING DIAGRAM

Refer to DTC P0335 on page

05-80

INSPECTION PROCEDURE

HINT:
Read freeze frame data using hand-held tester or OBD II scan tool. Because freeze frame records the en-
gine 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.

INSPECT CRANK POSITION SENSOR (See page

18-2

)

(a)

Check the output waveform.

Item

Contents

Terminal

CH1: VV1+

⇔

NE-

CH2: VV2+

⇔

VV2-

Equipment Set

5V/DIV, 20MS/DIV

Condition

During Cranking or idling

HINT:
The correct waveforms are as shown.

056H7-01

A57021

NE-

G22

E10

VV1+

VV2+

VV2-

A57020

VV1+

NE-

VVL-

VVL+

Bank 1

Bank 2

05-84

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

237

2002 LEXUS ES300 REPAIR MANUAL (RM911U)

REPLACE CRANK POSITION SENSOR

CHECK HARNESS AND CONNECTOR(ECM - CRANK POSITION SENSOR NO.1)

(a)

Disconnect the ECM E8 and E10 connector.

(b)

Disconnect the crank position sensor No.1 connector.

(c)

Check for continuity between terminals shown in the il-
lustration and table.
Standard (check for open) :

Sensor position

Crank position

sensor No.1

Connector terminal

ECM

Connector

terminal

Continuity

Bank 1

VV1+

Continuity

Bank 1

NE-

Continuity

Bank 2

Continuity

Bank 2

VVL+

VV2+

Continuity

Bank 2

VVL-

VV2-

Continuity

(Check for short)

Sensor position

Crank position

sensor No.1

Connector terminal

ECM

Connector

terminal

Continuity

Bank 1

VV1+

No Continuity

Bank 1

NE-

No Continuity

Bank 2

No Continuity

Bank 2

VVL+

No Continuity

Bank 2

VVL-

No Continuity

REPAIR OR REPLACE HARNESS AND
CONNECTOR

CHECK SENSOR INSTLLATION(CRANK POSITION SENSOR NO.1)

TIGHTEN SENSOR. REPLACE CAMSHAFT
TIMING GEAR

CHECK CAMSHAFT TIMING PULLEY

REPLACE CAMSHAFT TIMING PULLEY

CHECK AND REPLACE ECM

Waveform of
A/F Sensor

Normal Catalyst

Abnormal Catalyst

Waveform of Heated Oxygen
Sensor behind Catalyst

A01674

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-85

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2002 LEXUS ES300 REPAIR MANUAL (RM911U)

DTC

P0420

CATALYST SYSTEM EFFICIENCY BELOW
THRESHOLD (BANK1)

DTC

P0430

CATALYST SYSTEM EFFICIENCY BELOW
THRESHOLD (BANK2)

CIRCUIT DESCRIPTION

The ECM observes the waveform of the heated oxygen sensor located behind the catalyst to determine
whether the catalyst performance has deteriorated.
If the catalyst is functioning normally, the waveform of the heated oxygen sensor located behind the catalyst
switches back and forth between rich and lean much more slowly.
When the waveform of the heated oxygen sensor located behind the catalyst alternates flutteringly between
rich and lean, it indicates that catalyst performance has deteriorated.

DTC No.

DTC Detecting Condition

Trouble Area

P0420

After engine and catalyst are warmed up, and while vehicle is
driven within set vehicle and engine speed range, waveform of
heated oxygen sensor (bank 1 sensor 2) alternates flutteringly
between rich and lean (2 trip detection logic)

Gas leakage on exhaust system

A/F sensor (bank 1 sensor 1)

Heated oxygen sensor (bank 1 sensor 2)

Exhaust manifold

P0430

After engine and catalyst are warmed up, and while vehicle is
driven within set vehicle and engine speed range, waveform of
heated oxygen sensor (bank 2 sensor 2) alternates flutteringly
between rich and lean (2 trip detection logic)

Gas leakage on exhaust system

A/F sensor (bank 2 sensor 1)

Heated oxygen sensor (bank 2 sensor 2)

Exhaust manifold

051MA-06

Engine Speed

3,000 rpm

Idling

IG SW OFF

Warmed up

3 min. or so

Check

Time

(a)

2 sec.

2,000 rpm

(b)

(c)

(d)

2 sec.

A00479

05-86

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

239

2002 LEXUS ES300 REPAIR MANUAL (RM911U)

CONFIRMATION ENGINE RACING PATTERN

(a)

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

(b)

Start engine and warm it up with all the accessories switched OFF until the water temperature is stable.

(c)

Race the engine at 2,500 - 3,000 rpm for about 3 min.

(d)

When racing the engine at 3,000 rpm for 2 sec. and 2,000 rpm for 2 sec. alternately, check the wave-
form of the heated oxygen sensor (bank 1 sensor 2).

INSPECTION PROCEDURE

CHECK OTHER DTC OUTPUT (BESIDES DTC P0420, P0430)

(a)

Read the DTC using the hand-held tester or OBD II scan tool.

YES

GO TO RELEVANT DTC CHART

CHECK EXHAUST GAS LEAK

REPAIR OR REPLACE

CHECK AIR FUEL RATIO SENSOR (BANK1, 2 SENSOR1) (See page

12-1

)

REPAIR OR REPLACE AIR FUEL RATIO
SENSOR