Lexus ES300 (2002 year). Manual - part 49

70

Engine Control

10A
ETCS

From Power Source System (See Page 56)

1B

2

IL2

1

B

6

E

8

E

9

E

23

E

7

E

6

C

4

D

7

D

6

A

26

A

22

A

28

A

27

A

23

A

29

C

16

C

15

EE

I 6

E  2

E  2

E  2

E  2

E  2

E

10

11 E

E

12

13 E

3

2

3

2

3

2

3

2

3

2

3

2

L–

R

L–

R

R–

W

P

LG

–B

L–Y

G–

R

L

W–

R

W

–

R

W–

R

W–

R

W–

R

W–

R

W–

R

Ignition Coil
and Igniter No. 1

I 1

Ignition Coil
and Igniter No. 2

I 2

Ignition Coil
and Igniter No. 3

I 3

Ignition Coil
and Igniter No. 4

I 4

Ignition Coil
and Igniter No. 5

I 5

Ignition Coil
and Igniter No. 6

I 6

2

1

BR

BR

E01

E02

ME01

E04

E05

VCPA

VPA

EPA

VCP2

VPA2

EPA2

OC1+

OC1–

W–

B

W–

B

W–

B

W–

B

W–

B

R

L–

Y

LG

–B

B–

R

W–

R

LG

G–

B

G–

R

W–

B

W–

B

W–

B

W–

B

+BM

IGT1

IGT2

IGT3

IGT4

IGT5

IGT6

IGF

6

5

3

4

2

1

W–R

W–R

W–R

W–R

Accelerator Pedal Position Sensor

A25

V

V

T

 S

o

lenoi

d R

H

V1

0

Engine Control Module

E 6(A), E 7(B), E 8(C), E 9(D), E10(E)

VCP1

VPA1

EP1

VCP2

VPA2

EP2

W

W

IGT

IGF

IGT

IGF

IGT

IGF

IGT

IGF

IGT

IGF

IGT

IGF

1H

4

1K

9

L–

R

71

IF7

2

IF4

17

IF4

18

IF4

16

IF7

6

IK1

6

A

19

A

11

A

18

A

5

A

12

B

14

B

17

B

15

B

27

B

26

B

16

B

34

C

8

B

3

CODE

RXCK

TXCT

Y–G

B–O

V–W

G–R

W

P–B

R

G–

W

R–

L

L–

Y

V

L

G–

W

L–W

V–

W

G–

R

Y–

G

B–

O

W

P–

B

R

4

3

5

Transponder Key
Computer

I13

1

IF4

22

IF4

7

IF4

8

IF4

9

IF4

10

IK1

3

IK1

8

IF4

4

3B

3B

98

118

3B

3B

58

78

(*2)
(*3)

3B

3B

78

98

B

1

A

15

B

33

B

31

A

31

A

25

A

30

A

24

A

17

C

10

B

26

C

9

C

18

C

11

C

20

P

o

w

e

r S

teer

ing 

O

il

Pr

e

s

s

u

re

 SW

P 3

Skid Control ECU

S 6(B), S 7(C)

R–

W

BR

–

W

W

B

G

L

P–

L

B

BR

BR

BR

BR

–

W

W

B

G

L

P–

L

B

BR

BR

IL1

16

PS

NEO

ENG+

ENG–

TRC+

TRC–

A/CS

A/CI

EOM

HP

CODE

RXCK

TXCK

IMLD

KSW

CF

ACMG

SPD

W

THWO

TACH

SIL

TC

WFSE

NEO

ENG+

ENG–

TRC+

TRC–

Engine Control Module

* 2 : w/ VSC
* 3 : w/o VSC

A

/C

 C

ont

ro

l

A

sse

m

b

ly

Un

lo

c

k

W

a

rn

ing S

W

F

A

N NO

. 1

Re

la

y

D

iode 

(A/

C

)

W

(*2)

A/CS

A/CI

(*3)

3B

3B

109

129

2

7

A/C Control Assembly

A14

C

14

C

13

1

2

OC2+

OC2–

L–R

L–

W

V

V

T

 S

o

lenoi

d LH

V 9

W

W

E 6(A), E 7(B), E 8(C), E 9(D), E10(E)

IK1

1

B

32

6

THR

Y–

B

Y–

B

AC1

72

Engine Control

2M

1

7. 5A
OBD

From Power Source System (See Page 56)

2A

4

IA

ID

3B

3B

71

91

3B

3B

32

52

3B

3B

51

71

3B

3B

52

72

A

40

A

33

B

2

A

11

A

31

A

21

Combination Meter

C 7(A), C 8(B)

3B

3B

64

84

3B

3B

60

80

3B

3B

54

74

(*2)
(*3)

3B

3B

50

70

2L

8

2R

8

W–

B

W

BR

W–

B

S

B

BR

SG

CG

Y–G

B–O

V–W

G–R

W

P–B

R

P–

B

W

W

W

W

WW

B

15

13

7

16

5

4

Data Link
Connector 3

D 2

*  2 : w/ VSC
*  3 : w/o VSC

WFSE

TC

SIL

BAT

(*3)

(*2)

10A
GAUGE1

(* 2)
(* 3)

(* 2)
(* 3)

BR

3A

82

3A

87

3A

92

3A

57

3B

3B

79

99

3B

3B

106

126

3B

3B

69

89

3B

3B

86

106

(*3)

(*2)

(*2)
(*3)

(* 2)
(* 3)

(* 2)
(* 3)

A

39

W

S

pee

dom

e

ter

G–

R

Ma

lfunc

ti

on

Indi

c

a

to

r La

m

p

Power

V–

W

Y–

G

B–

O

W

T

a

ch

om

et

er

Micro Computer

73

This system utilizes an engine control module and maintains overall control of the engine, transmission and so on. An outline
of the engine control is explained here.

1. Input Signals

(1) Engine coolant temp. signal circuit

The engine coolant temp. sensor detects the engine coolant temp. and has a built–in thermistor with a resistance which
varies according to the water temp. is input into TERMINAL THW of the engine control module as a control signal.

(2) Intake air temp. signal circuit

The intake air temp. sensor is installed in the mass air flow meter and detects the intake air temp., which is input as a
control signal into TERMINAL THA of the engine control module.

(3) Oxygen sensor signal circuit

The oxygen density in the exhaust gases is detected and input as a control signal into TERMINALS OX1B and OX2B of
the engine control module. To maintain stable detection performance by the heated oxygen sensor, a heater is used for
warming the sensor. The heater is also controlled by the engine control module (HT1B and HT2B).

(4) RPM signal circuit

Camshaft position and crankshaft position are detected by the VVT sensor RH and crankshaft position sensor. The
camshaft position is input as a control signal to TERMINAL VV1+ of the engine control module, and the engine RPM is
input into TERMINAL NE+.

(5) Throttle signal circuit

The throttle position sensor detects the throttle valve opening angle as a control signal, which is input into TERMINAL
VTA1 of the engine control module.

(6) Vehicle speed signal circuit

The vehicle speed sensor, detects the vehicle speed and input to ABS speed sensor of the skid control ECU (w/ VSC)
or skid control ECU with actuator (w/o VSC), from skid control ECU to TERMINAL SPD of the engine control module, Via
combinatio meter.

(7) Park/Neutral position SW signal circuit

The Park/Neutral position SW detects whether the shift position is in neutral, parking or not, and inputs a control signal
into TERMINAL NSW of the engine control module.

(8) A/C SW signal circuit

The A/C control assembly inputs the A/C operations into TERMINAL A/CS of the engine control module as a control
signal.

(9) Battery signal circuit

Voltage is always supplies to TERMINAL BATT of the engine control module.
If you turn on the ignition SW, the current goes from TERMINAL MREL of the engine control module to the EFI relay and
put on the relay, and the voltage related to the engine control module operation is supplied to TERMINAL +B of the
engine control module through the EFI relay.

(10) Intake air volume signal circuit

Intake air volume is detected by the mass air flow meter and a signal is input into TERMINAL VG of the engine control
module as a control signal.

(11) Starter signal circuit

To confirm whether the engine is cranking, the voltage applied to the starter motor during cranking is detected and the
signal is input into TERMINAL STA of the engine control module as a control signal.

(12) Engine knock signal circuit

Engine knocking is detected by the knock sensor No.1 and No.2, then the signals are input into TERMINALS KNKR and
KNKL of the engine control module as a control signal.

(13) Air fuel ratio signal circuit

The air fuel ratio is detected and input as a control signal into TERMINALS AFL+, AFR+ of the engine control module.

System Outline