ECU LEXUS GS400 2000 Service Service Manual

BE0G3±03
I01375
Garage Door Opener Switch
Engine Room No.1
Junction Block

ECU±B Fuse
Passenger Side
Junction Block

DOME Fuse
± BODY ELECTRICALGARAGE DOOR OPENER SYSTEM
BE±233
2534 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
LOCATION
The vehicle shown in this illustration is ºGS400º.
All components of ºGS300º other than the ones used for engine are same as ºGS400º.

BE0G7±07
START
Insert the key in the key cylinder.
Under registration
Registration completion
Remove the key.
Will you register the
next key?
NoSecurity indicator blinks until the first
key is inserted. The indicator light
lights up after the key registration.
Security Indicator ON
Security Indicator
OFF
END Ye s
Security Indicator ON
(After the last key (sub±key)
has been registered, the indi-
cator goes off.)
BE±238
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
2539 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
ENGINE IMMOBILISER SYSTEM
REGISTRATION PROCEDURE
1. KEY REGISTRATION IN AUTOMATIC REGISTRATION MODE
(a) Registration of a new transponder key.
HINT:

This must be done when you install a new ECM.

The new ECM is in the automatic key code registration mode. The already fixed number of key codes
for this ECM can be registered.
On this type of vehicle, up to 3 key codes can be registered.

In the automatic registration mode, the key registered last becomes the sub±key.

1.2 Sec.
0.8 Sec.
0.25 Sec. 0.5 Sec.0.25 Sec.
1 Sec. Blinks
Code 2±1 Code2±2
0.25 Sec.
0.25 Sec.0.5 Sec. 1 Sec.
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
BE±239
2540 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
HINT:

When a key is not inserted in the key cylinder in the automatic registration mode, the security indicator
always lights on.

When the immobiliser system operates normally and the key is pulled out, the security indicator blinks.

When key code registration could not be performed in the automatic registration mode, code 2±1 is
output from the security indicator and when inserting the already registered key, code 2±2 is output.
(b) Automatic registration mode completion
If completing the mode forcibly when more than 1 key code have been registered in the automatic reg-
istration mode, perform the following procedures.
After 1 more key code have been registered with master key, perform step (1) or (2) without pulling
the key out or inserting the already registered key.
(1) Depress and release brake pedal 5 times or more within 15 sec.
(2) With the LEXUS hand±held tester, require automatic registration mode completion.

Will you register the
next key?
No Ye s
Insert already registered master key in the key
cylinder
Depress and release the acceleration pedal 5
times.
Depress and release the brake pedal 6 times,
and remove the master key.
Insert key to be registered in key cylinder.
Depress and release the acceleration pedal 1
time. (Security indicator blinks.)
The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 secs. after
indicator has been OFF or 10 sec. have passed. Within 10 sec.Within 15 sec.
Within 20 sec.
Within 10 sec.
Within 10 sec.
After 60 sec. additional master key is registered.
(Security indicator is OFF.)
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
BE±241
2542 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(d) There are 2 ways for registration of additional master key, one way is depressing brake pedal and ac-
celeration pedal and the other way is using LEXUS hand±held tester.
HINT:

It is possible to register up to 7 master key codes including the already registered key code.

When any operation time described below is over, registration mode completes.

When the next procedure is performed while the timer is working, the timer completes counting time,
then next timer starts.

When replacing ºIgnition Cylinder Key Setº or ºLock Cylinder Setº register according to the following
procedure using the original master key. However, after the registration of the additional master key,
as the original master key and the original sub±key are not necessary any more, erase registered of
those key codes.
(1) Depressing brake pedal and acceleration pedal:

Will you register the
next key?
Insert already registered master key in the key cylinder.
Using LEXUS hand±held tester select master key regis-
tration.
Remove the master key.
Insert key to be registered in key cylinder.
(Security indicator blinks.)
After 60 sec., additional master key is registered.
(Security indicator OFF.)
No Ye s Within
10 sec.Within 120 sec.
Within 20 sec.
Within 10 sec.
The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 secs. after
indicator has been OFF or 10 sec. have passed.
BE±242
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
2543 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(2) Using LEXUS hand±held tester:

Will you register the
next key?
No Ye s
Insert already registered master key in the key
cylinder
Depress and release the acceleration pedal 4
times.
Depress and release the brake pedal 5 times,
and remove the master key.
Insert key to be registered in key cylinder.
Depress and release the acceleration pedal 1
time. (Security indicator blinks.)
Within 10 sec.Within 15 sec.
Within 20 sec.
Within 10 sec.
Within 10 sec.
After 60 sec. additional sub±key is registered.
(Security indicator is OFF.)
The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 secs. after
indicator has been OFF or 10 sec. have passed.
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
BE±243
2544 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. REGISTRATION OF ADDITIONAL SUB±KEY
There are 2 ways for registration of additional sub±key, one way is depressing brake pedal and acceleration
pedal and the other way is using LEXUS hand±held tester.
HINT:

It is possible to register up to 3 sub±key codes including the already registered key code.

When any operation time described below is over, registration mode completes.

When the next procedure is performed while the timer is working, the timer completes counting time,
then next timer starts.
(1) Depressing brake pedal and acceleration pedal:

Will you register the
next key?
Insert already registered master key in the key cylinder.
Using LEXUS hand±held tester select sub±key registra-
tion.
Remove the master key.
Insert key to be registered in key cylinder.
(Security indicator blinks.)
After 60 sec., additional sub±key is registered.
(Security indicator OFF.)
No Ye s Within
10 sec.Within 120 sec.
Within 20 sec.
Within 10 sec.
The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 secs. after
indicator has been OFF or 10 sec. have passed.
BE±244
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
2545 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(2) Using LEXUS hand±held tester:

1. Insert master key in the key cylinder.
2. Require key code deletion from hand±held tester.
(Security indicator blinks)
3. Remove the master key.
HINT:
When the key cannot be pulled out in the step 3, key code deletion is canceled.
(Security indicator is OFF.) END
(Key code erased.)
Within 120 sec.
Within 10 sec.
BE±246
± BODY ELECTRICALENGINE IMMOBILISER SYSTEM
2547 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
(2) Using LEXUS hand±held tester:

BE19B±01
± BODY ELECTRICALTROUBLESHOOTING
BE±3
2304 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
TROUBLESHOOTING
PROBLEM SYMPTOMS TABLE
IGNITION SWITCH AND KEY UNLOCK WARNING SWITCH
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
Ignition Switch:
SymptomSuspect AreaSee page
Ignition switch is not set to each position.4. Ignition switch
5. Power source circuitBE±31
±
Key Unlock Warning Switch:
SymptomSuspect AreaSee page
Key unlock warning system does not operate.
(The buzzer does not sound when the driver's door is opened with
the ignition OFF and key inserted)1. Key Unlock Warning Switch
2. Door Courtesy Switch
3. Wire HarnessBE±31
BE±60
±
Key unlock warning system does not operate.
(The buzzer sounds when the ignition key is ACC or ON)1. Ignition Switch
2. Wire HarnessBE±31
±
HEADLIGHT AND TAILLIGHT SYSTEM:
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
HINT:
To inspect the bulb and light control ECU, replace them with the ones working normally and judge whether
they work normally or not.
SymptomSuspect AreaSee page
ºAutomatic light control systemº does not operate.
1. Automatic Light Control Sensor
2. Light Control Switch
3. Door Courtesy Switch
4. Wire Harness
5. Body No.2 ECUBE±37
BE±37
BE±60
±
DI±820
Auto turn±off system does not operate when the driver's door is
opened.1. Drivers Door Courtesy SwitchBE±60
Auto turn±off system:
Headlight and taillight do not come on.1. Body ECU No.2
2. Wire HarnessDI±820
±
Auto turn±off system:
Headlight and taillight stay on.1. Body ECU No.2
2. Wire HarnessDI±820
±
USA:
SymptomSuspect AreaSee page
Only one headlight comes on.
1. Bulb
2. *Light Control ECU
3. Wire Harness±
±
±
ºLO±Beamº does not light (All).
1. Headlight Control Relay
2. *Light Control ECU
3. Wire HarnessBE±37
±
±
ºLO±Beamº does not light (One side).
1. Bulb
2. H±LP L±LWR Fuse
3. H±LP R±LWR Fuse
4. *Light Control ECU
5. Wire Harness±
BE±21
BE±21
±
±
ºHI±Beamº does not light (All).1. Headlight Dimmer Switch
2. Wire HarnessBE±37
±

BE±4
± BODY ELECTRICALTROUBLESHOOTING
2305 Author: Date:
2000 LEXUS GS300/GS400 (RM718U) ºHI±Beamº does not light (One side).
1. Bulb
2. H±LP L±UPR Fuse
3. H±LP R±UPR Fuse
4. Wire Harness±
BE±21
BE±21
±
ºFlashº does not light.
1. H±LP L±UPR Fuse
2. H±LP R±UPR Fuse
3. Headlight Dimmer Switch
4. *Light Control ECU
5. Wire HarnessBE±21
BE±21
BE±37
±
±
ºFlashº does not light.
1. Bulb
2. *Light Control ECU
3. Wire Harness±
±
±
Headlight does not come on.
1. Headlight Control Relay
2. Light Control Switch
3. *Light Control ECU
4. Wire HarnessBE±37
BE±37
±
±
Headlight does not come on.
1. Bulb
2. *Light Control ECU
3. Wire Harness±
±
±
Headlight flickers.
1. Bulb
2. *Light Control ECU
3. Wire Harness±
±
±
Headlight is dark.
1. Bulb
2. *Light control ECU
3. Wire Harness±
±
±
Only one taillight comes on.1. Bulb
2. Wire Harness±
±
Taillight does not come on.
(Headlight is normal)
1. TAIL Fuse
2. GAUGE Fuse
3. Taillight Control Relay
4. Light Failure Relay
5. Light Control Switch
6. Wire HarnessBE±21
BE±21
BE±37
BE±92
BE±37
±
Taillight does not come on.
(Headlight does not light)1. Light Control Switch
2. Wire HarnessBE±37
±
Rear combination light does not come on.
1. Light Failure Relay
2. Wire Harness
3. BulbBE±92
±
±
*: HID Type
CANADA:
SymptomSuspect AreaSee page
Only one headlight comes on.
1. Daytime Running Light No.2, 3, 4 Relay
2. Daytime Running Light Main Relay
3. Bulb
4. *Light Control ECU
5. Wire HarnessBE±37
BE±37
±
±
±
ºLO±Beamº does not light (All).
1. Headlight Control Relay
2. *Light Control ECU
3. Wire HarnessBE±37
±
±
ºLO±Beamº does not light (One side).
1. Bulb
2. H±LP L±LWR Fuse
3. H±LP R±LWR Fuse
4. *Light Control ECU
5. Wire Harness±
BE±21
BE±21
±
±