TOYOTA SEQUOIA 2001 Service Repair Manual

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

DI±790
± DIAGNOSTICSAIR SUSPENSION SYSTEM
984 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Inspect height control manual indicator lamp.
PREPARATION:
Turn the ignition switch to the ON position.
CHECK:
Check that the height control manual indicator lamp comes on.
OK:
Height control manual indicator lamp comes on, and then goes off after 2 seconds.
NG Go to combination meter
(See page DI±1610).
OK

I27705
Combination Meter Wire Harness View:
C6
C6±13
F16805
Suspension Control ECU
Wire Harness View:
S25
VN
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±791
985 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check harness and connector (Suspension control ECU ± Combination meter
assy).
PREPARATION:
Disconnect the suspension control ECU connector and the
combination meter connector.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Tester connection
(Symbol)ConditionSpecified condition
S25±11 (VN) ± C6±13AlwaysBelow 1 W
S25±11 (VN) ±
Body groundAlways10 kW or higher
NG Repair or replace harness or connector.
OK

F16805
Suspension Control ECU
Wire Harness View:
S25
VN
DI±792
± DIAGNOSTICSAIR SUSPENSION SYSTEM
986 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check combination meter.
PREPARATION:
Reconnect the combination meter connector.
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Tester connection
(Symbol)ConditionSpecified condition
S25±11 (VN) ±
Body groundIgnition switch ON10 to 14 V
NG Replace combination meter
(See page IN±35).
OK
Replace suspension control ECU
(See page IN±35).

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

DI±794
± DIAGNOSTICSAIR SUSPENSION SYSTEM
988 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
Start the inspection from step 1 when using the hand±held tester, and start from step 2 when not using the
hand±held tester.
1 Read value of the hand±held tester.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON, and push the hand±held tester main switch ON.
(c) Select the item ºIG VOLTAGEº in the DATA LIST, and read its value displayed on the hand±held tester.
AIR SUSPENSION:
ItemMeasurement Item / Range (Dis-
play)Normal ConditionDiagnostic Note
IG VOLTAGEECU power supply voltage / min.:
0 V, max.: 25.5 VActual ECU power supply voltage:
10 to 14 V±
CHECK:
Check the ECU supply voltage.
OK:
Actual ECU power supply voltage: 10 to 14 V
OK Proceed to next circuit inspection shown in
problem symptoms table (See page DI±716).
NG

F16805
Suspension Control ECU
Wire Harness View:
S25
IG
± DIAGNOSTICSAIR SUSPENSION SYSTEM
DI±795
989 Author: Date:
2005 SEQUOIA (RM1146U)
2 Inspect suspension control ECU.
PREPARATION:
Disconnect the ECU connector.
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Tester connection
(Symbol)ConditionSpecified condition
S25±10 (IG) ±
Body groundIgnition switch OFF " ONBelow 1 V " 10 to 14 V
RESULT:
NGA
OK (When checking from step 1)B
OK (When checking from step 2)C
B Replace suspension control ECU
(See page IN±35).
C Proceed to next circuit inspection shown in
problem symptoms table (See page DI±716).
A
Repair or replace harness or connector.

DIDJT±01
F19148
Combination Meter
Tire Pressure
Warning Lamp DI±796
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
990 Author: Date:
2005 SEQUOIA (RM1146U)
TIRE PRESSURE WARNING SYSTEM
PRECAUTION
NOTICE:
When disconnecting the battery terminal, initialize the following system after the terminal is recon-
nected.
System NameSee Page
Back Door Power Window Control SystemBE±77
1. TIRE PRESSURE WARNING SYSTEM PRECAUTION
(a) When the tire pressure warning lamp comes on, immedi-
ately check the tire pressure of the tire and adjust it to the
specified pressure. (The tire pressure warning lamp
comes on if there is an open in the tire pressure warning
lamp circuit.)
NOTICE:
Check the spare tire as well since this system monitors
pressure of all tires, including the spare.
Tire sizeFrontRearSpare
P245 / 70 R 16220 kPa (2.2 kgf/cm2, 32 psi)240 kPa (2.4 kgf/cm2, 35 psi)240 kPa (2.4 kgf/cm2, 35 psi)
P265 / 70 R 16220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)
P265 / 65 R 17220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)220 kPa (2.2 kgf/cm2, 32 psi)
(b) When the tire pressure warning lamp blinks, there is a
malfunction in the system. Check for DTCs.
(c) It is necessary to register the transmitter ID in the tire pres-
sure monitor ECU when replacing the tire pressure moni-
tor valve sub±assy and/or tire pressure monitor ECU (see
page DI±805).
(d) When replacing the tire pressure monitor ECU.
(1) Using the DATA LIST, read the transmitter IDs regis-
tered in the ECU and make a note of them before
removing the tire pressure monitor ECU.
(2) Register the transmitter IDs after installing a new
tire pressure monitor ECU.
(e) When replacing the tire pressure monitor valve sub±assy.
(1) Make a note of the 7 digit number (transmitter ID)
written on the tire pressure monitor valve sub±assy
when replacing the tire pressure monitor valve sub±
assy. Register the transmitter IDs in the tire pres-
sure monitor ECU after replacing the tire pressure
monitor valve sub±assy and installing the tires and
wheels on the vehicle.

F19132
Transmitter ID
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
DI±797
991 Author: Date:
2005 SEQUOIA (RM1146U)
NOTICE:
The transmitter ID is written on the tire pressure monitor
valve sub±assy and ID can not be seen after installing the
tire pressure monitor valve sub±assy on the tire and wheel.
Therefore, make a note of the transmitter ID before instal-
ling the tire pressure monitor valve sub±assy.
2. IN CASE OF TIRE AND WHEEL REPLACEMENT
(a) When tires and wheels are replaced, register the transmitter ID without fail.
3. IN CASE OF TIRE ROTATION OR REPLACEMENT OF TIRE PRESSURE MONITOR ECU, TIRE
PRESSURE MONITOR VALVE SUB±ASSY, OR TIRES WITH DIFFERENT TIRE PRESSURE
(a) Initialize the tire pressure warning system after one of the following is performed:

Replacing the tire pressure monitor ECU or the tire pressure monitor valve sub±assy

Tire rotation

Replacing tires with different tire pressure
HINT:
The tire pressure warning system will not operate properly if it is not initialized (see page DI±808).
4. FAIL±SAFE FUNCTION
(a) When a system malfunction occurs in the tire pressure warning system, the tire pressure warning lamp
blinks and informs the driver of the system failure.
(b) The result of this diagnosis is stored in the tire pressure monitor ECU.

DIDJU±01
F19149
Tire Pressure Sensor
(Tire Pressure Monitor
Valve Sub±assy)
Tire Pressure Sensor
(Tire Pressure Monitor
Valve Sub±assy)Tire Pressure Sensor
(Tire Pressure Monitor
Valve Sub±assy) Combination Meter Assy

Tire Pressure Warning Lamp
Tire Pressure
Monitor ECU
Tire Pressure Warning
Reset Switch
Tire Pressure Sensor
(Tire Pressure Monitor Valve Sub±assy) Tire Pressure Sensor
(Tire Pressure Monitor
Valve Sub±assy)
Tire Pressure Monitor
Receiver Assy
DI±798
± DIAGNOSTICSTIRE PRESSURE WARNING SYSTEM
992 Author: Date:
2005 SEQUOIA (RM1146U)
LOCATION