horn LEXUS GS400 2000 Service User Guide

BE0FZ±08
I04195
I04196
6
I04197
BE±250
± BODY ELECTRICALHORN SYSTEM
2551 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. INSPECT HORN SWITCH
(a) Disconnect the negative (±) terminal from the battery.
(b) Remove the left and right covers from the steering wheel.
(c) Using a torx socket wrench, loosen the 2 bolts.
(d) Pull up the horn pad and place it on the steering column,
as shown.
HINT:
Do not disconnect the connector from the horn pad.
(e) Disconnect the connector from the slip ring.
(f) Check that no continuity exists between terminal 6 of the
connector and body ground.
(g) Check that continuity exists between terminal 6 of the
connector and body ground when the horn contact plate
is pressed against the steering spoke assembly.
If continuity is not as specified, repair or replace the steering
wheel or wire harness as necessary.
(h) Install the horn pad in place and using a torx socket
wrench, torque the 2 bolts.
Torque:
7.1 N´m (72 kgf´cm, 62 in.´lbf)
(i) Install the left and right covers.
(j) Connect the negative (±) terminal to the battery.
2. INSPECT HORN OPERATION
Connect the positive (+) lead from the battery to the terminal
and negative (±) lead to the horn body and check that the horn
blows.
If operation is not as specified, replace the horn.
3. INSPECT HORN SWITCH CIRCUIT
(See page DI±806)

I01200
2 1
35
2 5
1 3
± BODY ELECTRICALHORN SYSTEM
BE±251
2552 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
4. INSPECT HORN RELAY CONTINUITY
ConditionTester connectionSpecified condition
Constant1 ± 2Continuity
Apply B+ between
terminals 1 and 2.3 ± 5Continuity
If continuity is not as specified, replace the relay.
5. INSPECT HORN RELAY CIRCUIT
(See page BE±21)

BE±12
± BODY ELECTRICALTROUBLESHOOTING
2313 Author: Date:
2000 LEXUS GS300/GS400 (RM718U) The system does not operate when the ignition switch is turned to
ACC without using a key or transmitter.
1. Ignition Switch
2. Key Unlock Warning Switch
3. Transmitter
4. Wire Harness
5. Body No.1 ECUBE±31
BE±31
BE±157
±
DI±776
Some of the system does not operate.
(Headlight does not light up.)
1. Headlight System
2. Wire Harness
3. Body No.2 ECU
4. Body No.1 ECUBE±3
±
DI±820
DI±776
Some of the system does not operate.
(Taillight does not light up.)
1. Taillight System
2. Wire Harness
3. Body No.2 ECU
4. Body No.1 ECUBE±3
±
DI±820
DI±776
Some of the system does not operate.
(Theft Deterrent Horn or Horn does not sound.)
1. HORN Fuse
2. Theft Deterrent Horn
3. Horn
4. Horn Relay
5. Wire Harness
6. Body No.1 ECUBE±21
BE±150
BE±250
BE±250
±
DI±776
While the warning is given, the system cannot be canceled by
unlocking the door with key or transmitter.1. Door Key Lock and Unlock Switch
2. Wire Harness
3. Body No.1 ECUBE±131
±
DI±776
While the warning is given, the system cannot be canceled by
turning the ignition switch to ACC or ON with key.
1. Ignition Switch
2. Key Unlock Warning Switch
3. RAD NO.2 Fuse
4. ECU±IG Fuse
5. Wire Harness
6. Body No.2 ECU
7. Body No.1 ECUBE±31
BE±31
BE±21
BE±21
±
DI±820
DI±776
The system operates for more than 60 seconds.Body No.1 ECUDI±776
WIRELESS DOOR LOCK CONTROL SYSTEM
This system uses the multiplex communication system, so check diagnosis system of the multiplex commu-
nication system before you proceed with troubleshooting.
HINT:
Troubleshooting of the wireless door lock control system is based on the premise that the door lock
control system is operating normally. Accordingly, before troubleshooting the wireless door lock control
system, first make certain that the door lock control system is operating normally.
If the trouble still reappears even though there are no abnormalities in any of the other circuits, then
check and replace the Wireless Door Lock Control Receiver as the last step.
SymptomSuspect AreaSee page
All functions of wireless door lock control system do not operate.
1. Transmitter
2. Wireless Door Lock Control Receiver
3. Wire Harness
4. Body No.1 ECUBE±157
BE±157
±
DI±776
Wireless door lock operates, but the buzzer does not sound.
(The buzzer does not sound when the customize function prohib-
its.)1. Wireless Door Lock Buzzer
2. Wireless Door Lock Control Receiver
3. Wire HarnessBE±157
BE±157
±

± BODY ELECTRICALTROUBLESHOOTING
BE±15
2316 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
GARAGE DOOR OPENER SYSTEM
SymptomSuspect AreaSee page
The equipment of which code has been registered does not oper-
ate.1. Garage Door Opener Switch
2. Wire Harness
3. *BE±235
±
±
LED does not light up. (Even though either switch is pressed.)1. Garage Door Opener Switch
2. Wire HarnessBE±235
±
LED does not light up. (Only one switch is pressed.)Garage Door Opener SwitchBE±235
* As the GARAGE DOOR OPENER on the vehicle side seems to be normal, check the OPENER on the
equipment side, of which code has been registered.
ENGINE IMMOBILIZER SYSTEM
SymptomSuspect AreaSee page
Engine immobilizer system does not operate.See DIAGNOSIS SYSTEMDI±726
HORN SYSTEM
SymptomSuspect AreaSee page
Horn system does not operate.
1. HORN Fuse
2. Horn Relay
3. Horn Switch
4. Horn
5. Wire HarnessBE±21
BE±250
BE±250
BE±250
±
Horns blow all the time.
1. Horn Relay
2. Horn Switch
3. Wire HarnessBE±250
BE±250
±
One horn operates but the other horn does not operate.1. Horn
2. Wire HarnessBE±250
±
Horns operate abnormally.
1. Horn Relay
2. Horn
3. Wire HarnessBE±250
BE±250
±

MA002±06
MA±2
± MAINTENANCEINSIDE VEHICLE
45 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSIDE VEHICLE
GENERAL MAINTENANCE
These are maintenance and inspection items which are considered to be the owner's responsibility.
They can be done by the owner or they can have them done at a service shop.
These items include those which should be checked on a daily basis, those which, in most cases, do not
require (special) tools and those which are considered to be reasonable for the owner to do.
Items and procedures for general maintenance are as follows.
1. GENERAL NOTES

Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.

Every service item in the periodic maintenance schedule must be performed.

Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).

Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.

Failure to do even one item an cause the engine to run poorly and increase exhaust emissions.
2. LIGHTS
(a) Check that the headlights, stop lights, taillights, turn signal lights, and other lights are all working.
(b) Check the headlight aiming.
3. WARNING LIGHTS AND BUZZERS
Check that all warning lights and buzzers function properly.
4. HORN
Check that it is working.
5. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
6. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
7. WINDSHIELD DEFROSTER
Check that air comes out from the defroster outlet when operating the heater or air conditioner.
8. REAR VIEW MIRROR
Check that it is mounted securely.
9. SUN VISORS
Check that they move freely and are mounted securely.
10. STEERING WHEEL
Check that it has the specified freeplay. Be alert for changes in steering condition, such as hard steering,
excessive freeplay or strange noises.
11. SEATS
(a) Check that all front seat controls such as seat adjusters, seatback recliner, etc. operate smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the locks hold securely in any latched position.
(d) Check that the head restraints move up and down smoothly and that the locks hold securely in any
latches position.
(e) For folding±down rear seat backs, check that the latches lock securely.
12. SEAT BELTS
(a) Check that the seat belt system such as the buckles, retractors and anchors operate properly and
smoothly.
(b) Check that the belt webbing is not cut, frayed, worn or dameged.

RS089±02
H04699
H02587
H03708
Horn Button Contact Plate
H04699
± SUPPLEMENTAL RESTRAINT SYSTEMSTEERING WHEEL PAD AND SPIRAL CABLE
RS±15
2246 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
INSPECTION
1. VEHICLES NOT INVOLVED IN COLLISION
(a) Do a diagnostic system check.
(See page DI±552)
(b) Do a visual check which includes the following items with
the steering wheel pad (with airbag) installed in the ve-
hicle.
Check cuts, minute cracks or marked discoloration on the
steering wheel pad top surface and in the grooved por-
tion.
2. VEHICLE INVOLVED IN COLLISION AND AIRBAG IS
NOT DEPLOYED
(a) Do a diagnostic system check.
(See page DI±552)
(b) Do a visual check which includes the following items with
the steering wheel pad (with airbag) removed from the ve-
hicle.

Check for cuts, minute cracks or marked discolor-
ation on the steering wheel pad top surface and in
the grooved portion.

Check for cuts and cracks in wire harness, and chip-
ping in connectors.

Check for the deformation of the horn button con-
tact plate of the steering wheel.
HINT:

If the horn button contact plate of the steering wheel is de-
formed, never repair it. Always replace the steering wheel
assembly with a new one.

There should be no interference between the steering
wheel pad and steering wheel, and the clearance should
be uniform all the way around when the new steering
wheel pad is installed on the steering wheel.
CAUTION:
For removal and installation of the steering wheel pad, see
the SR section and be sure to follow the correct procedure.

RS±16
± SUPPLEMENTAL RESTRAINT SYSTEMSTEERING WHEEL PAD AND SPIRAL CABLE
2247 Author: Date:
2000 LEXUS GS300/GS400 (RM718U)
3. VEHICLE INVOLVED IN COLLISION AND AIRBAG IS
DEPLOYED
(a) Do a diagnostic system check.
(See page DI±552)
(b) Do a visual check which includes the following items with
the steering wheel pad (with airbag) removed from the ve-
hicle.

Check for the deformation on the horn button con-
tact plate of the steering wheel.

Check for the damage on the spiral cable connector
and wire harness.
HINT:

If the horn button contact plate of the steering wheel is de-
formed, never repair it. Always replace the steering wheel
assembly with a new one.

There should be no interference between the steering
wheel pad and steering wheel, and the clearance should
be uniform all the way around when the new steering
wheel pad is installed on the steering wheel.