Lexus ES300 (1997 year). Manual — part 407

DI01U–01

Details of Problem

The theft deterrent system cannot be set

Inspecting Circuit*1

See page

DI–406

1. Indicator light circuit

2. ECU power source circuit

3. Key unlock warning switch circuit

7. Door courtesy switch circuit

8. Door unlock detection switch circuit

9. Luggage compartment door opener
main switch and opener switch circuit

The indicator light does not blink when system is set

Indicator light circuit

When the
system is
set

When the rear door is unlocked

When the luggage compartment door is opened
by a method other than the key

4. Luggage compartment door key
lock and unlock switch circuit

5. Luggage compartment door
courtesy switch circuit

When the engine hood is opened

The system
does not
operate

Door unlock detection switch circuit

3. Luggage compartment door
courtesy switch circuit

Engine hood courtesy switch circuit

While the system is
in warning operation

Horns do not sound

Theft deterrent horn does not sound

Headlights do not flash

Taillights do not flash

The starter cut is not cut off

The door lock is not locked in unlock condition

Horn relay circuit

Theft deterrent horn circuit

Headlight control relay circuit

Taillight control relay circuit

Starter relay circuit

Door unlock detection switch circuit

6. Door key lock and unlock switch
circuit

It is not canceled when the ignition key is turned to
ACC or ON position

It still operates when the luggage compartment door is
opened with the key

When the
system is
set

Ignition switch circuit

Luggage compartment door key
lock and unlock switch circuit

System is still set even when a rear door is open

Door courtesy switch circuit

Even when the
system is not
set

Horns sound

Theft deterrent horn sounds

Headlights stay on

Taillights stay on

Horn relay circuit

Theft deterrent horn circuit

Headlight control relay circuit

Taillight control relay circuit

DI–408

DI–423

DI–425

DI–427

DI–433

DI–437

DI–435

DI–431

DI–406

DI–435

DI–427

DI–439

DI–415

DI–413

DI–417

DI–419

DI–411

DI–435

DI–421

DI–425

DI–437

DI–415

DI–413

DI–417

DI–419

*1: If numbers are given to the circuit proceed with troubleshooting in the order indicated by those numbers.

10. Engine hood courtesy switch circuit

DI–439

1. Luggage compartment door opener
main switch and opener switch circuit

2. Luggage compartment door
opener motor circuit

DI–429

DI–431

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

DI–405

557

1997 LEXUS ES300 (RM511U)

PROBLEM SYMPTOMS TABLE

Proceed to the reference page shown in the matrix chart below for each malfunction symptom and trouble-
shoot for each circuit.
HINT:
Troubleshooting of the theft deterrent system is based on the premise that the door lock control system is
operating normally. Accordingly, before troubleshooting the theft deterrent system, first make certain that
the door lock control system is operating normally.

DI01V–01

N22059

A/C Control Assembly

Theft Deterrent ECU

IND

T4

10

R–Y

IJ1

4

R–Y

A14

5

N22046

2

1

DI–406

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

558

1997 LEXUS ES300 (RM511U)

CIRCUIT INSPECTION

Indicator Light Circuit

CIRCUIT DESCRIPTION

When the theft deterrent system is preparing to set, this circuit lights up the indicator light. When the system
has been set, it continually turns the indicator light on for 1 second and turns it off for 1 second, thus blinking
the indicator light.

WIRING DIAGRAM

INSPECTION PROCEDURE

1

Check indicator light.

PREPARATION:
(a)

Remove A/C control assembly.

(b)

Disconnect indicator light connector.

CHECK:
Connect the positive (+) lead to terminal 1 and the negative (–)
lead to terminal 2 of indicator light connector.
OK:
Indicator light comes on.

NG

Replace indicator light.

OK

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

DI–407

559

1997 LEXUS ES300 (RM511U)

2

Check harness and connector between theft deterrent ECU and indicator light,
indicator light and body ground (See page

IN–27

).

NG

Repair or replace harness or connector.

OK

Check and replace theft deterrent ECU.*1

*1: When there is a malfunction that the theft deterrent system
cannot be set, proceed to the next numbered circuit inspection
shown on matrix chart (See page

DI–405

).

N22060

Theft Deterrent ECU

E

J/C

J/C

A

A

A

IG

A

+B1

J35

C

E/G Room J/B No.2

FL BLOCK

C

FL MAIN
3.0 W

Battery

1

11

4

ALT

1

1

Instrument Panel J/B

Instrument Panel J/B

J16

J/C

J6

J5

T4

T3

R

L–W

L–W

1

1W

8

1G

12
2J

R

R

1

2A

SHORT PIN

7.5A DOME

1

1D

4
1B

25A DOOR

B–R

F11

F6

F8

B

100A

B–G

W–B

W–B

+B2

1

T3

DI–408

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

560

1997 LEXUS ES300 (RM511U)

ECU Power Source Circuit

CIRCUIT DESCRIPTION

This circuit provides power to operate the theft deterrent ECU.

WIRING DIAGRAM

DI01W–01