2001 TOYOTA SEQUOIA horn

DI±1766
± DIAGNOSTICSBODY CONTROL SYSTEM
1960 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check horn relay (See page BE±145).
NG Replace horn relay.
OK
5 Check wire harness and connector between horn and body ECU, body ECU and
horn switch (See page IN±35).
NG Repair or replace wire harness or connector.
OK
Proceed to next circuit inspection shown in
problem symptoms table
(See page DI±1686).

DI±1966
± DIAGNOSTICSAUDIO SYSTEM
2160 Author: Date:
2005 SEQUOIA (RM1146U)
5. Identify the condition in which the noise occurs, and check the noise filter on the related part.
Condition in which noise occursNoise Source
Depressing the acceleration pedal increases the noise, and stopping the
engine stops the noise immediately.Generator
Noise occurs during A/C or the heater operation.Blower motor
Rapid acceleration while driving on an unpaved road or after the ignition
switch is turned on makes noise.Fuel pump
Pressing and then releasing the horn switch, and keeping pressing the horn
switch makes unusual noise.Horn
Quiet noise is heard while the engine is running, but stops with the engine.Ignition
Noise occurs synchronously with the turn signal flash.Flasher
Noise occurs during window washer operation.Washer
Noise occurs while the engine is running, and it continues even after the en-
gine stops.Engine coolant temperature sensor
Noise occurs during wiper operation.Wiper
Noise occurs when the brake pedal is depressed.Stop light switch
Others.Static electricity stored on the vehicle
Reference:

Make sure first that there is no noise from outside. Failing to do so makes the noise source detec-
tion difficult and leads to misdiagnosis.

The noise should be removed in descending order of loudness.

Tuning the radio so that no station is received wakes the noise more noticeable, making the rec-
ognition of the phenomenon easier.

± DIAGNOSTICSAUDIO SYSTEM
DI±2027
2221 Author: Date:
2005 SEQUOIA (RM1146U)
Noise occurs
INSPECTION PROCEDURE
1 Check of speaker installation.
CHECK:
Check if each speaker is securely installed.
OK:
Each speaker is securely installed.
HINT:
The radio is equipped with a noise prevention system that blocks excessively loud noise. If such noise oc-
curs, check the all wiring is proper and that the antenna installation part ground and noise±prevention equip-
ment are installed.
Condition in which noise occursNoise type
Noise increases when the accelerator pedal is depressed, but stops when
the engine is stopped.Generator noise
Noise occurs during A/C or the heater operation.Blower motor noise
Noise occurs when the vehicle accelerates rapidly on an unpaved road or
after the ignition switch is turned on.Fuel pump noise
Noise occurs when the horn switch is pressed and released or when pressed
and held.Horn noise
Quiet noise occurs while the engine is running, but stops when the engine is
stopped.Ignition noise
Noise occurs synchronously with the blink of the turn signal.Flasher noise
Noise occurs during window washer operation.Washer noise
Noise occurs while the engine is running, and it continues even after the en-
gine is stopped.Water temperature sensor noise
Noise occurs during wiper operation.Wiper noise
Noise occurs when the brake pedal is depressed.Stop light switch noise
Others.Static electricity stored on the vehicle
HINT:

Identify the condition under which the noise occurs, and check the noise filter on the related part.

First ensure that the noise is not coming from the outside. Failure to do so makes noise source detec-
tion difficult and may lead to a misdiagnosis.

Noise should be removed in descending order of loudness.
NG Install it properly.
OK
Identification of noise source (See page DI±1964).
DIDA3±01

± DIAGNOSTICSNAVIGATION SYSTEM
DI±2233
2427 Author: Date:
2005 SEQUOIA (RM1146U)
Abnormal noise occurs
INSPECTION PROCEDURE
1 Check speaker installation
CHECK:
Check if each speaker is securely installed.
OK:
Each speaker is securely installed.
HINT:
The radio is equipped with a noise prevention system that blocks only excessively loud noise. If loud noise
occurs, check that all wiring is proper and that the antenna installation part ground and noise±prevention
equipment are installed.
Conditions under which noise occursNoise type
Noise increases when the accelerator pedal is depressed, but stops when
the engine is stopped.Generator noise
Noise occurs during A/C or heater operation.Blower motor noise
Noise occurs when the vehicle accelerates rapidly on an unpaved road or
after the ignition switch is turned on.Fuel pump noise
Noise occurs when the horn switch is pressed and released or when pressed
and held.Horn noise
Quiet noise is occurs while the engine is running, but stops when the engine
is stopped.Ignition noise
Noise occurs synchronously with the blink of the turn signal.Flasher noise
Noise occurs during window washer operation.Washer noise
Noise occurs while the engine is running, and continues even after the engine
is stopped.Water temperature sensor noise
Noise occurs during wiper operation.Wiper noise
Noise occurs when the brake pedal is depressed.Stop light switch noise
Others.Static electricity stored on the vehicle
HINT:

Identify the condition under which the noise occurs, and check the noise filter on the relevant part.

First ensure that the noise is not coming from outside. Failure to do so makes noise source detection
difficult and may lead to a misdiagnosis.

Noise should be removed in descending order of loudness.
NG Install it properly.
OK
Identification of noise source (See page DI±2174).
DIDCO±01

SR1KD±01
F17124
Screw CaseTorx® Screw
F17904
Correct
Wrong
Airbag Connectors
F06699
Matchmarks
SST
SR±14
± STEERINGTILT STEERING COLUMN
3241 Author: Date:
2005 SEQUOIA (RM1146U)
REMOVAL
1. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
Wait for 90 seconds after disconnecting the cable to prevent the
airbag working.
2. REMOVE STEERING WHEEL PAD
NOTICE:
If the airbag connector is disconnected with the ignition
switch in the ACC or ON position, DTCs will be recorded.
(a) Place the front wheels facing straight ahead.
(b) Remove the steering wheel lower No. 3 cover.
(c) Remove the steering wheel lower No. 2 cover.
(d) Using a torx® socket wrench (T30), loosen the 2 torx®
screws.
HINT:
Loosen each screw until the groove along the screw circumfer-
ence is caught on the screw case.
(e) Pull out the wheel pad from the steering wheel.
(f) Using a screwdriver, disconnect the airbag connectors.
CAUTION:

When storing the steering wheel pad, keep the upper
surface of the pad facing upward.

Never disassemble the steering wheel pad.
NOTICE:
When removing the steering wheel pad, take care not to
pull the airbag wire harness.
(g) Disconnect the horn terminal and remove the steering
wheel pad.
3. REMOVE STEERING WHEEL
(a) Remove the steering wheel set nut.
(b) Put matchmarks on the steering wheel and main shaft as-
sembly.
(c) Using SST, remove the wheel.
SST 09950±50013 (09951±05010, 09952±05010,
09953±05020, 09954±05021)
4. REMOVE UPPER AND LOWER COLUMN COVERS
Remove the 3 screws, upper and lower column covers.

F17129
Torx® Screw
Screw Case
± STEERINGTILT STEERING COLUMN
SR±25
3252 Author: Date:
2005 SEQUOIA (RM1146U)
15. INSTALL STEERING WHEEL
(a) Align the matchmark on the wheel with the one on the
main shaft.
(b) Install the wheel set nut.
Torque: 50 N´m (510 kgf´cm, 37 ft´lbf)
16. INSTALL STEERING WHEEL PAD
NOTICE:

Never use airbag parts from another vehicle. When
replacing parts, replace with new ones.

Make sure that the wheel pad is installed with the spe-
cified torque.

If the wheel pad has been dropped, or there are
cracks, dents or other defects on the case or connec-
tor, replace the wheel pad with a new one.

When installing the wheel pad, take care that the wir-
ings do not interfere with other parts and are not
pinched between other parts.
(a) Connect the horn terminal.
(b) Connect the airbag connectors.
(c) Install the wheel pad after confirming that the circumfer-
ence groove of the torx® screw is caught on the screw
case.
(d) Using a torx® socket wrench (T30), tighten the 2 torx®
screws.
Torque: 8.8 N´m (90 kgf´cm, 78 in.´lbf)
(e) Install the steering wheel lower No. 2 cover.
(f) Install the steering wheel lower No. 3 cover.
17. CHECK STEERING WHEEL CENTER POINT
18. CONNECT CABLE TO NEGATIVE BATTERY TERMI-
NAL
19. PERFORM INITIALIZATION (See page IN±20)
Some systems need initialization when disconnecting the cable
from the negative battery terminal.

H24695
RS117±01
H20642
H23201
Horn Button Contact Plate
H24696
RS±22
± SUPPLEMENTAL RESTRAINT SYSTEMSTEERING WHEEL PAD AND SPIRAL CABLE
3305 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION
1. VEHICLE NOT INVOLVED IN COLLISION
(a) Perform a diagnostic system check (see page DI±1147).
(b) With the steering wheel pad installed on the vehicle, per-
form a visual check. If there are any defects as mentioned
below, replace the steering wheel pad with a new one:
Cuts, minute cracks or marked discoloration on the steer-
ing wheel pad top surface or in the grooved portion.
2. VEHICLE INVOLVED IN A COLLISION AND AIRBAG IS
NOT DEPLOYED
(a) Perform a diagnostic system check (see page DI±1147).
(b) With the steering wheel pad removed from the vehicle,
perform a visual check. If there are any defects as men-
tioned below, replace the steering wheel pad or steering
wheel assembly with a new one:

Cuts, minute cracks or marked discoloration on the
steering wheel pad top surface or in the grooved
portion.

Cracks or other damage to the connectors.

Deformation of the steering wheel assembly.

Deformation of the horn button contact plate of the horn
button assembly.

There should be no interference between the steering
wheel pad and steering wheel assembly, and the clear-
ance should be uniform all the way around when a new
steering wheel pad is installed on the steering wheel as-
sembly.
CAUTION:
For removal and installation procedures of the steering
wheel pad, see page RS±21 and RS±31. Be sure to follow
the correct procedure.

BE±10
± BODY ELECTRICALTROUBLESHOOTING
3414 Author: Date:
2005 SEQUOIA (RM1146U) Some of the system does not operate.
(Taillight does not come on.)
1. TAIL Fuse
2. TAILLIGHT Relay
3. Light Control Switch
4. Wire Harness
5. Body ECUBE±14
BE±27
BE±27
±
±
Some of the system do not operate.
(Theft deterrent horn or vehicle horn does not sound.)
1. HORN Fuse
2. SECURITY HORN Fuse
3. HORN Relay Circuit
4. Theft Deterrent Horn Circuit
5. Horn
6. Body ECUBE±14
BE±14
BE±145
BE±92
BE±145
±
While the warning is given, the system cannot be canceled by
unlocking the door with a key or transmitter.
1. Door Key Lock and Unlock Switch Circuit (Driver Door
ECU)
Door Key Lock and Unlock Switch Circuit (Passenger
Door ECU)
Door Key Lock and Unlock Switch Circuit (Back Door
ECU)
2. Body ECUDI±1794
DI±1832
DI±1882
±
*1: w/ Glass breakage sensor
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 operates normally. Accordingly, before troubleshooting the wireless door lock control
system, first make certain that the door lock control system operates normally.
If the trouble still reappears even though there are no abnormalities in any of the other circuits, 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 Circuit
3. Body ECUBE±98
DI±1737
±
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 Circuit
2. Body ECUDI±1741
±
POWER SEAT CONTROL SYSTEM (w/o Driving Position Memory)
SymptomSuspect AreaSee page
Both Driver and Passenger Power seats do not operate.1. PWR SEAT Fuse
2. Wire HarnessBE±14
±
Driver's seat does not operate.1. Power Seat Switch (D)
2. Wire HarnessBE±109
±
Passenger's seat does not operate.1. Power Seat Switch (P)
2. Wire HarnessBE±109
±
ºSlide operationº does not operate.
1. Power Seat Switch (D, P)
2. Slide Motor (D, P)
3. Wire HarnessBE±109
BE±109
±
ºFront Vertical Operationº does not operate.
1. Power Seat Switch (D)
2. Front Vertical Motor (D)
3. Wire HarnessBE±109
BE±109
±
ºLifter Operationº does not operate.
1. Power Seat Switch (D)
2. Lifter Motor (D)
3. Wire HarnessBE±109
BE±109
±