2001 TOYOTA SEQUOIA wiring diagram

F19446
W
41G±Y1
4A11
4AG±Y27
S25 STP
BatteryB ALT
85 W 1
1L STOP 2
1FS14
Stop Light Switch
Sub J/B No. 4Suspension Control
ECU
Instrument Panel J/BF10
Fusible Link Block
1L
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±767
961 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1782/82 Stop Light Switch Circuit (Test Diagnosis)
CIRCUIT DESCRIPTION
When the brake pedal is depressed, the stop light comes on and the signal is input to the STP terminal of
the suspension control ECU.
HINT:
This DTC is output only when the sensor signal check is done.
DTC No.DTC Detecting ConditionTrouble Area
C1782/82The signal from the stop light switch assy does not change.

Stop light switch assy

Stop light switch circuit

Suspension control ECU
WIRING DIAGRAM
DIDE7±01

F19447
Body ECUSuspension Control
ECU
ACTY20
B631
S25 DOOR R DI±770
± DIAGNOSTICSAIR SUSPENSION SYSTEM
964 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1783/83 Door Courtesy Switch Circuit
(Test Diagnosis)
CIRCUIT DESCRIPTION
The door courtesy light switch turns on when the door is opened and turns off when the door is closed.
The signal is sent from the body ECU and the back door ECU into the DOOR terminal of the suspension
control ECU when any door is open.
HINT:
This DTC is output only when the sensor signal check is done.
For courtesy light switch connection, see the system diagram on page DI±698.
DTC No.DTC Detecting ConditionTrouble Area
C1783/83Door courtesy light switch signal does not change.

Door courtesy light switch

Back door lock assy (Back door courtesy light switch)

Door courtesy light switch circuit

Body ECU

Back door ECU

Suspension control ECU
WIRING DIAGRAM
DIDEA±01

F19448
H12
Height Control SwitchSuspension Control
ECU
IMS25 313
S25 HI
LOHSW
LW S
DNSW 32
4 2 W±BUPSW
W L±B
E DI±774
± DIAGNOSTICSAIR SUSPENSION SYSTEM
968 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1786/86 Height Control Switch Circuit
(Test Diagnosis)
CIRCUIT DESCRIPTION
Vehicle height can be chosen by pressing the height control switch.
By pressing the ºUPº side, vehicle height goes up.
By pressing the ºDOWNº side, vehicle height goes down.
HINT:
This DTC is output only when the sensor signal check is done.
DTC No.DTC Detecting ConditionTrouble Area
C1786/86Height control switch signal does not change.

Height control switch

Height control switch circuit

Suspension control ECU
WIRING DIAGRAM
DIDED±01

F19449
H17
Height Control Mode
Select SwitchSuspension Control
ECU
W±B
IM4BR±B
312
S25
TD DI±778
± DIAGNOSTICSAIR SUSPENSION SYSTEM
972 Author: Date:
2005 SEQUOIA (RM1146U)
DTC C1788/88 Height Control Mode Select Switch Circuit
(Test Diagnosis)
CIRCUIT DESCRIPTION
Height control can be operated or suspended by pressing the height control mode select switch.
By pressing the switch once, height control can be suspended.
By pressing the switch one more time, height control can be operated.
HINT:
The DTC is output only when the sensor signal check is done.
DTC No.DTC Detecting ConditionTrouble Area
C1788/88Height control mode select switch signal does not change.

Height control mode select switch

Height control mode select switch circuit

Suspension control ECU
WIRING DIAGRAM
DIDEF±01

F19450
C6
Combination
MeterSuspension Control
ECU
I18
Ignition SW Instrument Panel J/B
Engine Room J/B24
14
15
16 LO
N
HIP
B±L
GR±R26
S25
9
S25
8
S25LO
NR
HI
6
IG2 AM25
W±R B±R IGN1 11
7 1H
1J1C
1C32
W±R
AM2
1
2C
2D1
B
Battery B±O
B 5 4F10
FL Block
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±785
979 Author: Date:
2005 SEQUOIA (RM1146U)
Height Control Indicator Lamp Circuit
CIRCUIT DESCRIPTION
The height control indicator lamp indicates the target height, not the actual height.
It blinks when the height control is operated by pressing the height control switch and stays on when the
operation is completed.
WIRING DIAGRAM
DIDEL±01

F19451
C6
Combination
MeterSuspension Control
ECU
I18
Ignition SW
Engine Room J/B Instrument Panel J/B B±O
W±R11
7 1H
1JIGN1
1C
1C32
B±RMAN. 24
13 LG11
S25 VN
5
IG2 AM2 6
W±R
B
Battery 1
2D AM2
2C1
B5 4F10
FL Block
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±789
983 Author: Date:
2005 SEQUOIA (RM1146U)
Height Control Manual Indicator Lamp Circuit
CIRCUIT DESCRIPTION
When manual mode is selected by pressing the height control mode select switch, the manual indicator lamp
comes on. (For the wiring diagram of the height control mode select switch circuit, see page DI±778.) If the
suspension control ECU detects a problem, the height control manual indicator lamp blinks while suspend-
ing the height control function. At the same time, the suspension control ECU records a DTC in the memory.
Connect terminals TC and CG of the DLC3 to make the height control manual indicator lamp blink and output
DTCs.
WIRING DIAGRAM
DIDEN±01

F19452
Sub J/B No. 3Suspension Control
ECU
Instrument Panel J/BI18
Ignition SW
F10
FL BlockW±L 2
B
Battery IG1AM11 J37
AJ37
A J/C
B±R
S2510
IG
ALT5 8 W1L1
AM1
11C6 1C4 ECU±IG
1F4 B±R8
3A3C8
2B±YB±R
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±793
987 Author: Date:
2005 SEQUOIA (RM1146U)
IG Signal Circuit
CIRCUIT DESCRIPTION
The suspension control ECU, controlling the air suspension system, is activated when the ignition switch
is turned ON.
The main relay inside the ECU is activated after 2 seconds and the system is operated by +B power source.
WIRING DIAGRAM
DIDEO±01

F19171
Tire Pressure
Monitor ECU Tire Pressure Monitor
Valve Sub±assy Front LH
Tire Pressure Monitor
Valve Sub±assy Rear LH Tire Pressure Monitor
Valve Sub±assy Front RH
Tire Pressure Monitor
Valve Sub±assy Rear RHJ29A
H
J30 3
4
5 BD2
5
1
4 +5V
RDA
GNDL
V
BR±R T19
Tire Pressure
Monitor Receiver
BD2
BD2L
VL
RF5V
RDA
GND2
Tire Pressure Monitor
Valve Sub±assy SpareJ29C J29B
I
J30
J
J30 BR±RBR±R J/C
T178
T177
T1716 V
: Radio Signal
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
DI±835
1029 Author: Date:
2005 SEQUOIA (RM1146U)
CIRCUIT DESCRIPTION
The tire pressure monitor valve sub±assy constantly sends radio waves to the tire pressure monitor receiver
assy. If the battery for the tire pressure monitor valve sub±assy is depleted, or if the tire pressure monitor
receiver assy is defective or comes off, the DTC will be output. DTCs C2121/21 to C2125/25 can only be
deleted by the tester. DTCs C2181/81 to C2185/85 can be deleted when the transmitter sends a force trans-
mission signal or the test mode ends. DTCs C2181/81 to C2185/85 are output only in the test mode.
DTC No.DTC Detecting ConditionTrouble Area
C2121/21
C2122/22
C2123/23
C2124/24
C2125/25A DTC is detected when the ECU receives no signals for
51 minutes or more, the vehicle speed is 5 mph (8 km/h) or
higher, and the ECU receives no signals for 12 minutes or
more.
Tire pressure monitor receiver assy

Each tire pressure monitor valve sub±assy

Tire pressure monitor ECU

Wire harness
C2181/81
C2182/82
C2183/83
C2184/84
C2185/85
Malfunction in the transmitting/receiving circuit

Tire pressure monitor receiver assy

Each tire pressure monitor valve sub±assy

Tire pressure monitor ECU

Wire harness
HINT:
It is necessary to perform the procedure to identify the tire pressure monitor valve sub±assy that is malfunc-
tioning because it cannot be identified by the output DTC.
WIRING DIAGRAM