Lexus ES300 (1997 year). Manual — part 367

F00044

1

2

3

4

1

2

3

4

1

2

3

4

Open

Continuity

Continuity

(+)

(–)

–

DIAGNOSTICS

ANTI–LOCK BRAKE SYSTEM

DI–245

397

1997 LEXUS ES300 (RM511U)

3

Check ABS motor relay.

PREPARATION:
Remove ABS motor relay from Engine Room R/B No. 3.

CHECK:
Check continuity between each terminal of ABS motor relay.
OK:

Terminals 3 and 4

Continuity (Reference value 62

Ω

)

Terminals 1 and 2

Open

CHECK:
(a)

Apply battery positive voltage between terminals 3 and 4.

(b)

Check continuity between terminals of ABS motor relay.

OK:

Terminals 1 and 2

Continuity

NG

Replace ABS motor relay.

OK

4

Check for open and short in harness and connector between ABS motor relay
and ABS ECU (See page

IN–27

).

NG

Repair or replace harness or connector.

OK

If the same code is still output after the DTC is deleted, check the contact condition of each con-
nection.
If the connections are normal, the ECU may be defective.

F00083

Engine Room
R/B No. 3

Battery

MAIN

FL
Block

ALT

ABS
Solenoid
Relay

B–G

B–G

F6

F9

1

2

3

4

5

6

1

3

3

3

3

3

1

3

W–B

W–B

W–B

EA

EB

W–L

ABS
Actuator

A6

A5

A6

A5

A5

A5

A5

A5

A5

A5

A23

A23

A23

A23

A23

A23

A23

A23

A23

A23

GR

GR–R

DLC1

4

7

8

10

11

18

21

12

16

1

2

3

4

5

6

5

4

5

1

22

8

R–B

G–Y

L–B

W–R

LG–B

W–L

R–G

R

W–R

ABS ECU

SR

R+

SFRH

SRLH

SFLH

SRRH

SFRR

SRLR

SFLR

SRRR

AST

A23

1

2

ABS

Engine Room
R/B No. 3

Battery

MAIN

FL
Block

ALT

ABS
Solenoid
Relay

B–G

B–G

F6

F9

1

2

3

4

5

6

1

3

3

3

3

3

1

3

W–B

W–B

W–B

EA

EB

W–L

ABS
Actuator

A6

A5

A6

A5

A5

A5

A5

A5

A5

A5

A23

A23

A23

A23

A23

A23

A23

A23

A23

A23

GR

GR–R

DLC1

4

7

8

10

11

18

21

12

16

1

2

3

4

5

6

5

4

5

1

22

8

R–B

G–Y

L–B

W–R

LG–B

W–L

R–G

R

W–R

ABS ECU

SR

R+

SFRH

SRLH

SFLH

SRRH

SFRR

SRLR

SFLR

SRRR

AST

A23

1

2

ABS

DI–246

–

DIAGNOSTICS

ANTI–LOCK BRAKE SYSTEM

398

1997 LEXUS ES300 (RM511U)

DTC

21, 22, 23, 24

ABS Actuator Solenoid Circuit

CIRCUIT DESCRIPTION

This solenoid goes on when signals are received from the ECU and controls the pressure acting on the wheel
cylinders thus controlling the braking force.

DTC No.

DTC Detecting Condition

Trouble Area

21

Actuator solenoid SFRR or SFRH is open or short circuit

continues for 0.05 sec. or more.

ABS actuator

SFRR or SFRH circuit

22

Actuator solenoid SFLR or SFLH is open or short circuit

continues for 0.05 sec. or more.

ABS actuator

SFLR or SFLH circuit

23

Actuator solenoid SRRR or SRRH is open or short circuit

continues for 0.05 sec. or more.

ABS actuator

SRRR or SRRH circuit

24

Actuator solenoid SRLR or SRLH is open or short circuit

continues for 0.05 sec. or more.

ABS actuator

SRLR or SRLH circuit

Fail safe function: If trouble occurs in the actuator solenoid circuit, the ECU cuts off current to the ABS
solenoid relay and prohibits ABS control.

WIRING DIAGRAM

DI0BK–01

W00714

A6

A5

1

2

3

4

5

6

7

8

4

A6

A5

1

2

3

4

5

6

7

8

4

A6

A5

1

2

3

4

5

6

7

8

4

A6

A5

1

2

3

4

5

6

7

8

4

A6

A5

1

2

3

4

5

6

7

8

4

A6

A5

1

2

3

4

5

6

7

8

4

–

DIAGNOSTICS

ANTI–LOCK BRAKE SYSTEM

DI–247

399

1997 LEXUS ES300 (RM511U)

INSPECTION PROCEDURE

1

Check ABS actuator solenoid.

PREPARATION:
Disconnect the 2 connectors from ABS actuator.
CHECK:
Check continuity between terminals A6 – 4 and A5 – 1, 2, 3, 4,
5, 6, 7, 8 of ABS actuator connector.
OK:

Continuity

HINT:Resistance of each solenoid coil is 1.2

Ω

.

NG

Replace ABS actuator.

OK

2

Check for open and short in harness and connector between ABS ECU and
actuator (See page

IN–27

).

NG

Repair or replace harness or connector.

OK

If the same code is still output after the DTC is deleted, check the contact condition of each con-
nection.
If the connections are normal, the ECU may be defective.

BR3583
BR3582

F00010

Rotor

Speed Sensor

Magnet

To ECU

+V

–V

High Speed

Low Speed

Coil

N

S

DI–248

–

DIAGNOSTICS

ANTI–LOCK BRAKE SYSTEM

400

1997 LEXUS ES300 (RM511U)

DTC

31, 32, 33, 34

Speed Sensor Circuit

CIRCUIT DESCRIPTION

The speed sensor detects wheel speed and sends the ap-
propriate signals to the ECU. These signals are used to control
of the ABS system. The front and rear rotors each have 48
serrations.
When the rotors rotate, the magnetic field emitted by the perma-
nent magnet in the speed sensor generates an AC voltage.
Since the frequency of this AC voltage changes in direct propor-
tion to the speed of the rotor, the frequency is used by the ECU
to detect the speed of each wheel.

DTC No.

DTC Detecting Condition

Trouble Area

31, 32, 33, 34

Detection of any of conditions from (1) through (4):

(1) Vehicle speed is at 10 km/h (6 mph) or more and the

speed sensor signal circuit is open or short circuit

continues for 15 sec. or more.

(2) Momentary interruption of the speed sensor signal

occurs 7 times or more.

(3) Vehicle speed is at 20 km/h (12mph) or more and

interference on the speed sensor signal continues for

5 sec. or more.

(4) Open circuit condition of the speed sensor signal circuit

continues for 0.5 sec. or more.

Right front, left front, right rear, left rear speed sensor

Each speed sensor circuit

Speed sensor rotor

HINT:
DTC No. 31 is for the right front speed sensor.
DTC No. 32 is for the left front speed sensor.
DTC No. 33 is for the right rear speed sensor.
DTC No. 34 is for the left rear speed sensor.
Fail safe function: If trouble occurs in the speed sensor circuit, the ECU cuts off current to the ABS solenoid
relay and prohibits ABS control.

DI0BL–01