2001 TOYOTA SEQUOIA horn wiring

DI1OG±31
I27698
B5B6
B7 BODY CONTROL ECU:
DI±1688
± DIAGNOSTICSBODY CONTROL SYSTEM
1882 Author: Date:
2005 SEQUOIA (RM1146U)
TERMINALS OF ECU
Symbols (Terminals No.)Wiring ColorTerminal DescriptionConditionSpecified Condition
KSW ± GND1
(B5±13 ± B6±6)Y±G ± W±BKey unlock warning
switch signalKey unlock warning switch ON
(Key inserted)Below 1 V
KSW ± GND1
(B5±13 ± B6±6)Y±G ± W±BKey unlock warning
switch signalKey unlock warning switch OFF
(Key not inserted)10 to 14 V
KSW2 ± GND1
(B5±15 ± B6±6)Y±G ± W±B
Key unlock warning
switch signal (Immobi-
lizer)Key unlock warning switch ON
(Key inserted)Below 1 V
KSW2 ± GND1
(B5±15 ± B6±6)Y±G ± W±B
Key unlock warning
switch signal (Immobi-
lizer)Key unlock warning switch OFF
(Key not inserted)10 to 14 V
HR ± GND1
(B7±18 ± B6±6)W±R ± W±BHorn switch signalHorn switch ONBelow 1 V
HR ± GND1
(B7±18 ± B6±6)W±R ± W±BHorn switch signalHorn switch OFF10 to 14 V
BDN ± GND1
(B6±15 ± B6±6)P±L ± W±BBack door power win-
dow motor (DOWN)Back door power window switch
DOWN positionBelow 1 V
BDN ± GND1
(B6±15 ± B6±6)P±L ± W±BBack door power win-
dow motor (DOWN)Back door power window switch
OFF or UP position10 to 14 V
BUP ± GND1
(B6±14 ± B6±6)W ± W±BBack door power win-
dow motor (UP)Back door power window switch
UP positionBelow 1 V
BUP ± GND1
(B6±14 ± B6±6)W ± W±BBack door power win-
dow motor (UP)Back door power window switch
OFF or DOWN position10 to 14 V
ACC ± GND1
(B7±10 ± B6±6)GR ± W±BIgnition switch (ACC)Ignition switch OFFBelow 1 V
ACC ± GND1
(B7±10 ± B6±6)GR ± W±BIgnition switch (ACC)Ignition switch ACC or ON10 to 14 V
BECU ± GND1
(B6±5 ± B6±6)W±R ± W±BBatteryAlways10 to 14 V
RLCY ± GND1
(B7±7 ± B6±6)R±W ± W±BCourtesy light switch
(Rear LH)Rear LH door courtesy light
switch ON (Open)Below 1 V
RLCY ± GND1
(B7±7 ± B6±6)R±W ± W±BCourtesy light switch
(Rear LH)Rear LH door courtesy light
switch OFF (Closed)10 to 14 V
RRCY ± GND1
(B5±8 ± B6±6)R±W ± W±BCourtesy light switch
(Rear RH)Rear RH door courtesy light
switch ON (Open)Below 1 V
RRCY ± GND1
(B5±8 ± B6±6)R±W ± W±BCourtesy light switch
(Rear RH)Rear RH door courtesy light
switch OFF (Closed)10 to 14 V
PCTY ± GND1
(B5±22 ± B6±6)LG±B ± W±BCourtesy light switch
(Front RH)Passenger door courtesy light
switch ON (Open)Below 1 V

I18735
1Body ECU
T1
Theft Deterrent Horn
IA114
R±G
B71
SH R±G DI±1734
± DIAGNOSTICSBODY CONTROL SYSTEM
1928 Author: Date:
2005 SEQUOIA (RM1146U)
Theft deterrent horn circuit
CIRCUIT DESCRIPTION
During warning of the theft deterrent system, the body ECU activates the theft deterrent horn.
WIRING DIAGRAM
DI57A±10

I24147
B7
HORN HORN Relay
2
1Body ECU
1
2D18
HR
HORN
B5 B±Y
6 C9
Horn SW
B54 F10
FL Block H8
Horn (low)
1
1 B B8
2H
7
2F5
3W±R W±R19
IA1
26
Battery H7
Horn (high)Engine Room J/B
B DI±1764
± DIAGNOSTICSBODY CONTROL SYSTEM
1958 Author: Date:
2005 SEQUOIA (RM1146U)
Horn circuit
CIRCUIT DESCRIPTION
The vehicle horn sounds when the horn switch is pressed. It also sounds as an alarm for the theft deterrent
system when the body ECU detects any alert condition.
WIRING DIAGRAM
DI94T±08

± 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