Lexus ES300 (1997 year). Manual - part 408

N20674

N20675

I00632

E/G Room J/B No.2

Instrument Panel J/B

DOME Fuse

DOOR Fuse

N20676

E (–)

+B1 (+)

+B2 (+)

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

DI–409

561

1997 LEXUS ES300   (RM511U)

INSPECTION PROCEDURE

1

Check DOME and DOOR fuse.

PREPARATION:
(a)

Remove DOME fuse from engine room junction block
No.2.

(b)

Remove DOOR fuse from instrument panel junction block
No.1.

CHECK:
Check continuity of DOME and DOOR fuse.
OK:

Continuity

NG

Check for short in all the harness and compo-
nents connected to the DOME and DOOR fuse
(See attached wiring diagram).

OK

2

Check voltage between terminals +B1, +B2 and E of theft deterrent ECU connec-
tor.

PREPARATION:
Disconnect the theft deterrent ECU connector.
CHECK:
Measure voltage between terminals +B1, +B2 and E of theft de-
terrent ECU connector.
OK:

Voltage: 10

∼

14V

OK

Proceed to next circuit inspection shown on
matrix chart (See page 

DI–405

).

DI–410

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

562

1997 LEXUS ES300   (RM511U)

NG

3

Check for open in harness and connector between ECU and body ground 
(See page 

IN–27

).

NG

Repair or replace harness or connector.

OK

Check and repair harness and connector be-
tween ECU and battery.

N22061

Theft Deterrent ECU

SRLY

9

T3

1

IG2

E/G Room J/B No.2

9

5

3

1

11

ST Relay

GR

W–B

W–B

2

1

3

5

40A MAIN

30A AM2

4

W–R

Instrument
Panel J/B

Instrument
Panel J/B

5 1K

1B

5

7

8

J/C

B

J8

C

J9

GR

10

IK2

GR

PNP
Switch

6

5

11 IK2

B–W

B–W

B

B

B–W

1K

1J

4

3

Ignition
Switch

ST

AR

TER

Battery

Starter

FL MAIN
3.0W

R

W–R

1

1

B–R

F6

F8

1

1

FL BLOCK

B

B

B–R

5A

2J

2L

2K

2D

2B

2A

S2

S1

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

DI–411

563

1997 LEXUS ES300   (RM511U)

Starter Relay Circuit

CIRCUIT DESCRIPTION

When the theft deterrent system is activated, contact (a) in the ECU becomes open, creating an open circuit
in terminal SRLY circuit and making the starter inoperative (starter cut).
In this condition, if one of the following operations is done, the contact (a) in the ECU is grounded, thus can-
celing the starter cut:

(1)

Unlock the front LH or RH door with key.

(2)

Unlock the doors with the wireless door lock control system.

WIRING DIAGRAM

DI01X–01

N20677

SRLY

(+)

(–)

DI–412

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

564

1997 LEXUS ES300   (RM511U)

INSPECTION PROCEDURE

HINT:
This troubleshooting is based on the premise that engine cranking occurs.
If the engine does not crank, proceed to the engine troubleshooting on EG–Section.

1

Check voltage between terminal SRLY of theft deterrent ECU connector and
body ground.

PREPARATION:
(a)

Disconnect the theft deterrent ECU connector.

(b)

PNP switch ON (Shift to N or P position).

CHECK:
Measure voltage between terminal SRLY of theft deterrent ECU
connector and body ground, when ignition switch is turned to
ST position.
OK:

Voltage: 10

∼

14V

NG

Check and repair harness and connector be-
tween starter and theft deterrent ECU
(See page 

IN–17

).

OK

Check and repair theft deterrent ECU.