Lexus ES300 (2002 year). Service manual — part 52

82

Electronically Controlled Transmission and A/T Indicator

LL

2L

DL

NL

RL

PL

8

4

7

5

2

1

3

3B

3B

100

120

3B

3B

110

130

3A

3A

94

94

3B

3B

101

121

3B

3B

91

111

3A

3A

104

104

3B

3B

107

127

3B

3B

103

123

3B

3B

43

63

3A

3A

110

110

3A

3A

90

90

3B

3B

83

103

3B

3B

89

109

3B

3B

81

101

3B

3B

80

100

IL1

22

IL1

20

IL1

21

IL1

18

IL2

2

IL1

19

2L

5

2R

5

3B

3B

104

124

3B

3B

84

104

A

37

A

34

A

36

B

22

A

35

A

15

B

23

A

16

(*1)
(*2)

(*1)
(*2)

Y

L–

W

W–

L

R–

B

R–

B

G–

W

W

B–

R

W

LG

–

B

W

W

W

Y

W–L

L–W

Y–B

R–B

R–L

W

W–

L

Y

L–

W

W

W

Y–

B

R–

B

W

W

A/T Indicator Light SW

A 4

R

RB

L–B

V–W

3B

3B

74

94

3A

3A

114

114

3B

3B

77

97

3B

3B

99

119

W

3B

87 3B

107

3A

92

3A

82

W

Y–

B

W–

L

Y

L–B

W

4

2

5

6

1

MT2

MT4

MTL

NSSL

NSSD

3

MTD

Transmission
Control SW

T 8

Combination Meter

C 7(A), C 8(B)

W

W

W

W

W

W

L

2

3

4

D

N

R

P

83

10A
GAUGE2

2B

6

10A
GAUGE1

2M

1

From Power Source System (See Page 56)

A

40

IA

W

W

W–

B

* 1 : w/ VSC
* 2 : w/o VSC

IL2

3

W

A

21

1 A

SB

3A

87

57 3A

3B

3B

54

74

3B

3B

64

84

(* 2)

(* 1)

(* 2)

(* 1)

3A

55

85 3A

ID

BR

2R

8

8 2M

SB

BR

SB

W

Combination Meter

C 7(A), C 8(B)

L–

W

B

10

(*2

)

5

Skid Control ECU
with Actuator

S 1

A

33

S

peedom

et

er

R–L

W

IF7

12

L–

W

(*2

)

R–

L

Power

PN

Micro Computer

84

Electronically Controlled Transmission and A/T Indicator

Previous automatic transaxle have selected each gear shift using mechanically controlled throttle hydraulic pressure,
governor hydraulic pressure and lock–up hydraulic pressure. The electronically controlled transmission, however, electrically
controls the line pressure, throttle pressure, lock–up pressure and accumulator pressure etc. through the solenoid valve. The
electronically controlled transmission is a system which precisely controls gear shift timing and lock–up timing in response to
the vehicle’s driving conditions and the engine condition detected by various sensors. It makes smooth driving possible by
shift selection for each gear which is the most appropriate to the driving conditions at that time, and by preventing downing,
squat and gear shift shock when starting off.

1. Gear Shift Operation

When driving, the engine warm up condition is input as a signal to TERMINAL THW of the engine control module from the
engine coolant temp. sensor and the vehicle speed signal is input to TERMINAL SPD of the engine control module. At the
same time, the throttle valve opening signal from the throttle position sensor is input to TERMINALS VTA1 and VTA2 of the
engine control module as throttle angle signal.
Based on these signals, the engine control module selects the best shift position for the driving conditions and sends current
to the electronically controlled transmission solenoid.

2. Lock–Up Operation

When each signal makes engine control module recognize that LOCK–UP condition is satisfied, the current flows from
engine control module TERMINAL DSL to electronically controlled transmission solenoid TERMINAL DSL. At the same time,
the current flows engine control module TERMINAL SL1+ to electroically controlled transmission solenoid TERMINAL SL1+
and from TERMINAL SL1– to engine control module TERMINAL SL1–. This works LOCK–UP solenoid to perform
LOCK–UP operation.

3. Stop Light SW Circuit

If the brake pedal is depressed (Stop light SW on) when driving in lock–up condition, a signal is input to TERMINAL STP of
the engine control module. The engine control module operates and cuts the current to the solenoid to release lock–up.

E6 (A), E7 (B), E8 (C), E9 (D), E10 (E) Engine Control Module

L–E1 : 10.0–14.0 volts (Ignition SW on and shift lever at L position)
2–E1 : 10.0–14.0 volts (Ignition SW on and shift lever at 2 position)

R–E1 : 10.0–14.0 volts (Ignition SW on and shift lever at R position)
D–E1 : 10.0–14.0 volts (Ignition SW on and shift lever at D position)

THO–E2 : Below 1.0 volts (Ignition SW on and AFT temperature 110

°

C (230

°

F)

A4 A/T Indicator Light SW

3–1 : Closed with shift lever in P position
3–2 : Closed with shift lever in R position
3–5 : Closed with shift lever in N position
3–7 : Closed with shift lever in D position
3–8 : Closed with shift lever in L position
3–4 : Closed with shift lever in 2 position

: Parts Location

Code

See Page

Code

See Page

Code

See Page

A4

36

E6

A

38

S1

37

C1

36

E7

B

38

S13

39

C7

A

38

E8

C

38

T3

37

C8

B

38

E9

D

38

T4

37

E1

A

36

E10

E

38

T8

39

E2

B

36

I14

39

E3

36

J11

39

: Relay Blocks

Code

See Page

Relay Blocks (Relay Block Location)

1

22

Engine Room R/B (Engine Compartment Left)

System Outline

Service Hints

85

: Junction Block and Wire Harness Connector

Code

See Page

Junction Block and Wire Harness (Connector Location)

1B

1C

25

Engine Room Main Wire and Engine Room J/B (Engine Compartment Left)

1J

g

g

(

g

)

1K

25

Engine Wire and Engine Room J/B (Engine Compartment Left)

1L

25

Engine Wire and Engine Room J/B (Engine Compartment Left)

2A

28

Instrument Panel Wire and Driver Side J/B (Lower Finish Panel)

2B

28

Instrument Panel Wire and Driver Side J/B (Lower Finish Panel)

2E

28

Engine Room Main Wire and Driver Side J/B (Lower Finish Panel)

2G

28

Engine Room Main Wire and Driver Side J/B (Lower Finish Panel)

2L

2M

29

Instrument Panel Wire and Driver Side J/B (Lower Finish Panel)

2R

(

)

3A

34 (w/ VSC)

3A

35 (w/o VSC)

Instrument Panel Wire and Passenger Side J/B (Instrument Panel Brace RH)

3B

34 (w/ VSC)

Instrument Panel Wire and Passenger Side J/B (Instrument Panel Brace RH)

3B

35 (w/o VSC)

: Connector Joining Wire Harness and Wire Harness

Code

See Page

Joining Wire Harness and Wire Harness (Connector Location)

IF5

IF6

46

Engine Room Main Wire and Instrument Panel Wire (Right Side of Steering Column Tube)

IF7

g

( g

g

)

IK1

48

Instrument Panel Wire and Instrument Panel Wire (Instrument Panel Reinforcement RH)

IL1

48

Engine Wire and Instrument Panel Wire (Behind the Glove Box)

IL2

48

Engine Wire and Instrument Panel Wire (Behind the Glove Box)

: Ground Points

Code

See Page

Ground Points Location

ED

44

Left Fender

EE

44

Left Side of Cylinder Head

EF

44

Intake Side of Cylinder Block

IA

46

Instrument Panel Reinforcement LH

ID

46

Instrument Panel Brace RH

: Splice Points

Code

See Page

Wire Harness with Splice Points

Code

See Page

Wire Harness with Splice Points

I2

48

Engine Room Main Wire

I6

48

Engine Wire