Lexus RX300 (MCU15). Service manual - part 304

Condition

Disarming
condition

Output by alarm system Output by immobilizer

With Key

Without key

Goes off

Output by checking
visually

Blinks

Goes off

Blinks

Goes off

Disarming preparation 
condition

Lights up

Blinks

Lights up

Arming condition

Alarming condition

Goes off

Lights up

Blinks

Blinks

Blinks

Lights up

Sensor operation starts:

Sensor operation stops:

When the condition for arming preparation condition is met.

When the condition is transformed to the disarming condition.

DI–448

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

LEXUS RX300   (RM785E)

(a)

Indicator light output:

HINT:
The indicator light might blink even under the disarming condi-
tion. (This is caused by output from the immobilizer)
The indicator always blink by output from the immobilizer at any
time under the arming condition.
Blinking frequency: 
0.2: ON    1.8 sec.: OFF

(b)

ON/OFF function of radar sensor:
(1)

Radar sensor operation condition:

(2)

Radar sensor ON/OFF switching function:
Every time the button of the wireless door lock sys-
tem is pressed under the arming preparation condi-
tion, sensor is switched ON/OFF.

Destination

Double lock

Compulsion door lock

Europe

RHD

Australia / General countries

LHD

f

X

X

X

X

f

f

f

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

DI–449

LEXUS RX300   (RM785E)

(c)

Compulsion door lock function.
(1)

This is a control function to lock a door forcibly to
prevent someone from invading in the vehicle when
the inner door lock knob is unlocked under the arm-
ing condition, that is, when the alarming starts.
In Europe, when a door is locked with a key the
alarm sounds, however doors are not locked forci-
bly.

(2)

The setting specifications of the compulsion door
lock function change as follows according to wheth-
er the double lock system is available or not.

DI614–04

I19166

Door Lock Assembly
D Door Unlock Detection Switch

Rear RH Door ECU

Back Door Unlock 
Detection Switch

Theft Deterrent ECU

Ignition Switch

Engine Hood Courtesy Switch

Theft Deterrent Indicator

Theft Deterrent Indicator

Ignition Switch

Door Lock Assembly
D Door Unlock Detection Switch

Instrument Panel J/B
D ECU–IG Fuse

Theft Deterrent 
Indicator

Passenger Door ECU

Drive Door ECU

Instrument Panel J/B
D EFI–IG Fuse

Except Europe:

RHD:

Europe:

LHD:

Rear LH Door ECU

Theft Deterrent ECU

DI–450

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

LEXUS RX300   (RM785E)

PARTS LOCATION

DI615–04

I01920

T5

T4

–

DIAGNOSTICS

THEFT DETERRENT SYSTEM

DI–451

LEXUS RX300   (RM785E)

TERMINALS OF ECU

Symbols (Terminals No.)

Wiring Color

Condition

STD Value

DSWH ↔ E

R W ↔ W B

Engine hood courtesy switch position is OFF. 

(Engine hood closed)

Below 1 V

DSWH ↔ E

(T4–4 ↔ T4–22)

R–W ↔ W–B

Engine hood courtesy switch position is ON. 

(Engine hood opened)

10 – 14 V

UL2 ↔ E

LG R ↔ W B

Back door key lock and unlock switch position is LOCK.

10 – 14 V

UL2 ↔ E

(T4–5 ↔ T4–22)

LG–R ↔ W–B

Back door key lock and unlock switch position is UNLOCK.

Below 1 V

S+B ↔ E

(T4–8 ↔ T4–22)

R–Y ↔ W–B

Constant

10 – 14 V

IG ↔ E

B R ↔ W B

Ignition switch position is LOCK or ACC.

Below 1 V

IG ↔ E

(T4–10 ↔ T4–22)

B–R ↔ W–B

Ignition switch position is ON.

10 – 14 V

+B1 ↔ E

(T4–11 ↔ T4–22)

  G–B*1

W–L*2 ↔ W–B

Constant

10 – 14 V

L2 ↔ E

L W ↔ W B

Back door key lock and unlock switch position is UNLOCK.

10 – 14 V

L2 ↔ E

(T4–13 ↔ T4–22)

L–W ↔ W–B

Back door key lock and unlock switch position is LOCK.

Below 1 V

IOUT ↔ E

W ↔ W B

Radar sensor detection invader

Below 1 V

IOUT ↔ E

(T4–18 ↔ T4–22)

W ↔ W–B

Constant

10 – 14 V

KSW ↔ E

L ↔ W B

Key is inserted.

Below 1 V

KSW ↔ E

(T4–19 ↔ T4–22)

L ↔ W–B

Key is not inserted.

10 – 14 V

E ↔ Body ground

(T4–22 ↔ Body ground)

W–B ↔ Body

ground

Constant

Below 1 V

HORN ↔ E

W R ↔ W B

Horn switch position is ON.

Below 1 V

HORN ↔ E

(T5–4 ↔ T4–22)

W–R ↔ W–B

Horn switch position is OFF.

10 – 14 V

CLTS ↔ E

L B ↔ W B

Theft deterrent sylstem change condition.

One time

CLTS ↔ E

(T5–9 ↔ T4–22)

L–B ↔ W–B

Contstant

10 – 14 V

TRIG ↔ E

Y ↔ W B

Theft deterrent system is alarming contidion.

Below 1 V

TRIG ↔ E

(T5–10 ↔ T4–22)

Y ↔ W–B

Constant

10 – 14 V

IND ↔ E

(T5–12 ↔ T4–22)

L ↔ W–B

During set preparation.

3 – 5 V

*1: LHD
*2: RHD