Lexus ES300 (1997 year). Manual — part 382

F00082

ALT

Engine Room R/B No. 3

2

ABS & TRAC
Motor Relay

A7

ABS & TRAC Actuator

ABS

4

W–R

MT

R+

GR–L

14

24

MR

A19

1

3

F9

F6

B–G

FL
Block

EB

MAIN

Battery

EA

1

B–G

3

3

3

1

2

3

A7

A7

1

2

3

W–B

W–B

W–B

A19

A19

GR–R

R–W

1

ABS & TRAC ECU

1

–

DIAGNOSTICS

ABS & TRACTION CONTROL SYSTEM

DI–305

457

1997 LEXUS ES300 (RM511U)

DTC

51

ABS Pump Motor Lock

CIRCUIT DESCRIPTION

DTC No.

DTC Detecting Condition

Trouble Area

51

In the midst of initial check, after the current flows to the

motor for 3 sec. and motor relay is turned OFF, then

within 0.66 sec., the condition that the motor relay

monitor is OFF continues for 0.24 sec. or more.

ABS pump motor

Fail safe function: If trouble occurs in the ABS & TRAC pump motor, the ECU cuts off current to the ABS &
TRAC solenoid relay and prohibits ABS control and TRAC control.

WIRING DIAGRAM

DI0CC–01

F00063

ECM

ABS & TRAC ECU

EFI+

EFI–

TRC+

TRC–

EFI+

EFI–

TRC+

TRC–

E7

E7

E7

E7

A20

A20

A20

A20

26

25

28

27

6

14

13

5

W

B

G

L

ECM

ABS & TRAC ECU

EFI+

EFI–

TRC+

TRC–

EFI+

EFI–

TRC+

TRC–

E7

E7

E7

E7

A20

A20

A20

A20

26

25

28

27

6

14

13

5

W

B

G

L

ECM

ABS & TRAC ECU

EFI+

EFI–

TRC+

TRC–

EFI+

EFI–

TRC+

TRC–

E7

E7

E7

E7

A20

A20

A20

A20

26

25

28

27

6

14

13

5

W

B

G

L

ECM

ABS & TRAC ECU

EFI+

EFI–

TRC+

TRC–

EFI+

EFI–

TRC+

TRC–

E7

E7

E7

E7

A20

A20

A20

A20

26

25

28

27

6

14

13

5

W

B

G

L

DI–306

–

DIAGNOSTICS

ABS & TRACTION CONTROL SYSTEM

458

1997 LEXUS ES300 (RM511U)

DTC

53

ECM Communication Circuit Malfunction

CIRCUIT DESCRIPTION

This circuit is used to send TRAC control information from the ABS & TRAC ECU to the ECM (TRC+, TRC–),
and engine control information from the ECM to the ABS & TRAC ECU (EFI+, EFI–).

DTC No.

DTC Detecting Condition

Trouble Area

53

ECM communication data malfunction is detected.

TRC+ or TRC– circuit

EFI+ or EFI– circuit

ECM

ABS & TRAC ECU

WIRING DIAGRAM

INSPECTION PROCEDURE

1

Check for open and short in harness and connector between terminals EFI+,
EFI–, TRC+, TRC– of ABS & TRAC ECU and ECM (See page

IN–27

).

NG

Repair or replace harness or connector.

OK

Check and replace ECM or ABS & TRAC ECU.

DI0CD–01

–

DIAGNOSTICS

ABS & TRACTION CONTROL SYSTEM

DI–307

459

1997 LEXUS ES300 (RM511U)

DTC

61

Engine Control System Malfunction

CIRCUIT DESCRIPTION

If trouble occurs in the engine control system, the ECU prohibits TRAC control.

DTC No.

DTC Detection Condition

Trouble Area

61

Conditions (1) and (2) is detected:

(1) ECM communication is normal, malfunction information

of engine system ON, and engine speed is 500 rpm or

more continues for 0.48 sec. or more, and TRAC

operation start condition is concluded.

(2) ECM communication is normal, malfunction information

of engine system is ON, engine speed is 500 rpm and

more continues for 1 sec. or more, and the engine

system memorizes DTC.

Engine control system

INSPECTION PROCEDURE

1

Check the DTC for the engine (See page

DI–3

).

*1

Repair engine control system according to the
code output.

*2

Check for ECU connected to malfunction indicator light.

*1: Output NG code
*2: Malfunction indicator light remains ON.

DI0CE–01

DI–308

–

DIAGNOSTICS

ABS & TRACTION CONTROL SYSTEM

460

1997 LEXUS ES300 (RM511U)

DTC

Always ON

ABS & TRAC ECU Malfunction

CIRCUIT DESCRIPTION

DTC No.

DTC Detecting Condition

Trouble Area

Always ON

ABS & TRAC ECU internal malfunction is detected.

ECU

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

INSPECTION PROCEDURE

1

Is DTC output?

Check DTC on page

DI–273

.

YES

Repair circuit indicated by the code output.

NO

2

Is normal code displayed?

YES

Check ABS & TRAC solenoid relay. Check for
short in harness and connector between sole-
noid relay and DLC1 (See page

IN–27

).

NO

3

Is ABS warning light go off?

YES

Check for open or short in harness and connec-
tor between ECU–IG fuse and ABS & TRAC ECU
(See page

IN–27

).

NO

DI0CG–01