2001 TOYOTA SEQUOIA ABS

IN0253
WRONG CORRECT
IN0252
WRONG CORRECT IN±6
± INTRODUCTIONREPAIR INSTRUCTIONS
6 Author: Date:
2005 SEQUOIA (RM1146U)
(k) Care must be taken when jacking up and supporting the
vehicle. Be sure to lift and support the vehicle at the prop-
er locations (See page IN±8).
Cancel the parking brake on the level place and
shift the transmission in N position.
When jacking up the front wheels of the vehicle, first
place stoppers behind the rear wheels.
When jacking up the rear wheels of the vehicle, first
place stoppers before the front wheels.
When either the front or rear wheels only should be
jacked up, set rigid racks and place stoppers in front
and behind of the other wheels on the ground.
After the vehicle is jacked up, be sure to support it
on rigid racks. It is extremely dangerous to do any
work on a vehicle raised on a jack, even for a job that
can be finished quickly.
(l) Observe the following precautions to avoid damage to the
following parts:
(1) Do not open the cover or case of the ECU unless
absolutely necessary. (If the IC terminals are
touched, the IC may be destroyed by static electric-
ity.)
(2) To disconnect vacuum hoses, pull off the end, not
the middle of the hose.
(3) To pull apart electrical connectors, pull on the con-
nector itself, not the wires.
(4) Be careful not to drop electrical components, such
as sensors or relays. If they are dropped on a hard
floor, they should be replaced and not reused.
(5) When steam cleaning an engine, protect the elec-
tronic components, air filter and emission±related
components from water.
(6) Never use an impact wrench to remove or install
temperature switches or temperature sensors.

IN0002
Example
± INTRODUCTIONREPAIR INSTRUCTIONS
IN±7
7 Author: Date:
2005 SEQUOIA (RM1146U)
(7) When checking continuity at the wire connector, in-
sert the tester probe carefully to prevent terminals
from bending.
(8) When using a vacuum gauge, never force the hose
onto a connector that is too large. Use a step±down
adapter for adjustment. Once the hose has been
stretched, it may leak air.
(m) Installation and removal of vacuum hose:
(1) When disconnecting vacuum hoses, use tags to
identify where they should be reconnected to.
(2) After completing a job, double check that the vacu-
um hoses are properly connected. A label under the
hood shows the proper layout.
(n) Bleeding of hydraulic brake booster system.
When repairing the hydraulic brake booster or ABS,
TRAC, VSC system, bleed the air out of the hydraulic
brake booster(See page BR±4).
(o) Unless otherwise stated, all resistance is measured at an
ambient temperature of 20°C (68°F). Because the resis-
tance may be outside specifications if measured at high
temperatures immediately after the vehicle has been run-
ning. Measurement should be made when the engine has
cooled down.

F09750
DLC3
Ts
CG
± INTRODUCTIONFOR ALL OF VEHICLES
IN±17
17 Author: Date:
2005 SEQUOIA (RM1146U)
(i) AIRBAG SENSOR ASSEMBLY
(1) Never reuse the airbag sensor assembly involved
in a collision when the SRS has deployed.
(2) The connectors to the airbag sensor assembly
should be connected or disconnected with the sen-
sor mounted on the floor. If the connectors are con-
nected or disconnected while the airbag sensor as-
sembly is not mounted to the floor, it could cause
undesired ignition of the supplemental restraint sys-
tem.
(3) Work must be started after 90 seconds from the
time the ignition switch is turned to the ºLOCKº posi-
tion and the negative (±) terminal cable is discon-
nected from the battery, even if only loosening the
set bolts of the airbag sensor assembly.
(j) WIRE HARNESS AND CONNECTOR
The SRS wire harness is integrated with the cowl wire har-
ness assembly and floor wire harness assembly. All the
connectors for the system are also a standard yellow col-
or. If the SRS wire harness becomes disconnected or the
connector becomes broken due to an accident, etc., re-
pair or replace it.
2. FOR VEHICLES EQUIPPED WITH VEHICLE SKID
CONTROL (VSC) SYSTEM
NOTICE:

Even if TRAC is initially OFF, it automatically be-
comes ON when the vehicle speed becomes about 30
km/h (19 mh) or more. Therefore, please drive in the
test mode to avoid dangerous situations caused by
the TRAC control.

VSC/ABS may be failed when the vehicle is driven on
the two±wheel chassis dynamo. Therefore, after driv-
ing on the chassis dynamo, please clear DTC before
normal driving. Please refer to the page DI±899 for the
method of clearing DTC.

Fasten the vehicle with the lock chain.
(a) Confirm VSC system is OFF.
(1) Turn the ignition switch OFF.
(2) Using SST, connect terminals Ts and CG of DLC3.
SST 09843±18040
(3) Start the engine.

B04770
IN±18
± INTRODUCTIONFOR ALL OF VEHICLES
18 Author: Date:
2005 SEQUOIA (RM1146U)
(4) Check that the VSC TRAC warning light blinks.
(5) After the measurement, remove the SST and re-
start the engine. At this time, make sure that the
VSC TRAC warning light is off.
(b) Notice in VSC operation.
(1) Removal and reinstallation of VSC±related compo-
nents may cause misadjustment of them. Do not re-
move or reinstall them unless necessary.
(2) When conducting VSC±related operations, do not
fail to make sure that the preparation and the finish-
ing of the operation are all performed in accordance
with the direction in this text.
3. FOR VEHICLES EQUIPPED WITH A CATALYTIC CONVERTER
CAUTION:
If a large amount of unburned gasoline flows into the converter, it may overheat and create a fire haz-
ard. To prevent this, observe the following precautions and explain them to your customer.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid running the engine at idle speed for more than 20 minutes.
(c) Avoid spark jump test.
(1) Perform spark jump test only when absolutely necessary. Perform this test as rapidly as possible.
(2) While testing, never race the engine.
(d) Avoid prolonged engine compression measurement.
Engine compression tests must be done as rapidly as possible.
(e) Do not run engine when fuel tank is nearly empty.
This may cause the engine to misfire and create an extra load on the converter.
(f) Avoid coasting with ignition turned off.
(g) Do not dispose of used catalyst along with parts contaminated with gasoline or oil.
4. IF VEHICLE IS EQUIPPED WITH MOBILE COMMUNICATION SYSTEM
For vehicles with mobile communication systems such as two±way radios and cellular telephones, observe
the following precautions.
(1) Install the antenna as far as possible away from the ECU and sensors of the vehicle's electronic
system.
(2) Install the antenna feeder at least 20 cm (7.87 in.) away from the ECU and sensors of the ve-
hicle's electronic systems. For details about ECU and sensor locations, refer to the section on
the applicable component.
(3) Do not wind the antenna feeder together with the other wiring as much as possible, also avoid
running the antenna feeder parallel with other wire harness.
(4) Check that the antenna and feeder are correctly adjusted.
(5) Do not install powerful mobile communication system.

IN01T±18
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±23
23 Author: Date:
HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS
GENERAL INFORMATION
A large number of ECU controlled systems are used in the SEQUOIA. In general, the ECU controlled system
is considered to be a very intricate system requiring a high level of technical knowledge and expert skill to
troubleshoot. However, the fact is that if you proceed to inspect the circuits one by one, troubleshooting of
these systems is not complex. If you have adequate understanding of the system and a basic knowledge
of electricity, accurate diagnosis and necessary repair can be performed to locate and fix the problem. This
manual is designed through emphasis of the above standpoint to help service technicians perform accurate
and effective troubleshooting, and is compiled for the following major ECU controlled systems:
The troubleshooting procedure and how to make use of it are described on the following pages.
SystemPage
1. EngineDI±1
2. Automatic TransmissionDI±515
3. Air Suspension Control SystemDI±695
4. Tire Pressure Warning SystemDI±796
5. ABS with EBD & BA & TRAC & VSC SystemDI±891
6. Can Communication SystemDI±1060
7. Supplemental Restraint SystemDI±1118
8. Power Seat Control System w/ Driving Position MemoryDI±1501
9. Cruise Control SystemDI±1536
10.Engine Immobilizer SystemDI±1570
11. Combination Meter SystemDI±1601
12.Sliding Roof SystemDI±1661
13.Body Control SystemDI±1678
14.Driver Door Control SystemDI±1778
15.Passenger Door Control SystemDI±1814
16.Back Door Control SystemDI±1850
17.Multiplex Communication SystemDI±1887
18.Audio SystemDI±1955
19.Rear Seat Audio SystemDI±2044
20.Rear Seat Entertainment SystemDI±2078
21.Navigation SystemDI±2159
22.Air Conditioning SystemDI±2297
FOR USING OBD II SCAN TOOL OR TOYOTA HAND±HELD TESTER

Before using the scan tool or tester, the scan tool's instruction book or tester's operator manual should
be read thoroughly.

If the scan tool or tester cannot communicate with ECU controlled systems when you have connected
the cable of the scan tool or tester to DLC3, turned the ignition switch ON and operated the scan tool,
there is a problem on the vehicle side or tool side.
(1) If communication is normal when the tool is connected to another vehicle, inspect the diagnosis
data link line (Bus
line) or ECU power circuit of the vehicle.
(2) If communication is still not possible when the tool is connected to another vehicle, the problem
is probably in the tool itself, so perform the Self Test procedures outline in the Tester Operator's
Manual.

IN±26± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
26 Author: Date:
2005 SEQUOIA (RM1146U)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the SEQUOIA fulfills various functions. The first function is the Diagnostic Trouble
Code Check in which a malfunction in the signal circuits to the ECU is stored in code in the ECU memory
at the time of occurrence, to be output by the technician during troubleshooting. Another function is the Input
Signal Check which checks if the signals from various switches are sent to the ECU correctly.
By using these check functions, the problem areas can be narrowed down quickly and troubleshooting can
be performed effectively. Diagnostic functions are incorporated in the following systems in the SEQUOIA.
SystemDiagnostic Trouble
Code CheckInput Signal Check
(Sensor Check)Diagnostic Test
Mode (Active Test)
1. Engine(with Check
Mode)
2. Automatic Transmission(with Check
Mode)
3. Air Suspension Control System(with Check
Mode)
4. Tire Pressure Warning System
5. ABS with EBD & BA & TRAC & VSC System
6. Can Communication System
7. Supplemental Restraint System(with Check
Mode)
8. Power Seat Control System w/ Driving Position Memory
9. Cruise Control System
10.Engine Immobilizer System
11. Combination Meter System
12.Sliding Roof System
13.Body Control System
14.Driver Door Control System
15.Passenger Door Control System
16.Back Door Control System
17.Multiplex Communication System
18.Audio System
19.Rear Seat Audio System
20.Rear Seat Entertainment System
21.Air Conditioning System
In diagnostic trouble code check, it is very important to determine whether the problem indicated by the diag-
nostic trouble code is still occurring or occurred in the past but returned to normal at present. In addition,
it must be checked in the problem symptom check whether the malfunction indicated by the diagnostic
trouble code is directly related to the problem symptom or not. For this reason, the diagnostic trouble codes
should be checked before and after the symptom confirmation to determine the current conditions, as shown
in the table on the next page. If this is not done, it may, depending on the case, result in unnecessary trouble-
shooting for normally operating systems, thus making it more difficult to locate the problem, or in repairs not
pertinent to the problem. Therefore, always follow the procedure in correct order and perform the diagnostic
trouble code check.

IN04Q±33
IN±40
± INTRODUCTIONTERMS
40 Author: Date:
2005 SEQUOIA (RM1146U)
TERMS
ABBREVIATIONS USED IN THIS MANUAL
AbbreviationsMeaning
ABSAnti±Lock Brake System
A/CAir Conditioner
ACAlternating Current
ACCAccessory
ACISAcoustic Control Induction System
ACMActive Control Engine Mount
ACSDAutomatic Cold Start Device
A.D.D.Automatic Disconnecting Differential
A/FAir±Fuel Ratio
AHCActive Height Control Suspension
ALRAutomatic Locking Retractor
ALTAlternator
AMPAmplifier
ANTAntenna
APPROX.Approximately
ASSYAssembly
A/T, ATMAutomatic Transmission (Transaxle)
AT FAutomatic Transmission Fluid
AUTOAutomatic
AUXAuxiliary
AV GAverage
AV SAdaptive Variable Suspension
B+Battery Voltage
BABrake Assist
BACSBoost Altitude Compensation System
BATBattery
BDCBottom Dead Center
B/LBi±Level
B/SBore±Stroke Ratio
BTDCBefore Top Dead Center
BVSVBimetallic Vacuum Switching Valve
CBCircuit Breaker
CCoCatalytic Converter For Oxidation
CCVCanister Closed Valve
CDCompact Disc
CFCornering Force
CGCenter Of Gravity
CHChannel
CKDComplete Knock Down
COMB.Combination
CPECoupe
CPSCombustion Pressure Sensor
CPUCentral Processing Unit
CRSChild Restraint System
CTRCenter
C/VCheck Valve
CVControl Valve
CWCurb Weight

IN±42
± INTRODUCTIONTERMS
42 Author: Date:
2005 SEQUOIA (RM1146U) H/B
Hatchback
H±FUSEHigh Current Fuse
HIHigh
HIDHigh Intensity Discharge (Head Lamp)
HSGHousing
HTHard Top
HWSHeated Windshield System
ICIntegrated Circuit
IDIIndirect Diesel Injection
IFSIndependent Front Suspension
IGIgnition
IIAIntegrated Ignition Assembly
INIntake (Manifold, Valve)
INTIntermittent
I/PInstrument Panel
IRSIndependent Rear Suspension
ISCIdle Speed Control
J/BJunction Block
J/CJunction Connector
KDKick±Down
LANLocal Area Network
LBLiftback
LCDLiquid Crystal Display
LEDLight Emitting Diode
LHLeft±Hand
LHDLeft±Hand Drive
L/H/WLength, Height, Width
LLCLong±Life Coolant
LNGLiquified Natural Gas
LOLow
LPGLiquified Petroleum Gas
LSDLimited Slip Differential
LSP & PVLoad Sensing Proportioning And Bypass Valve
LSPVLoad Sensing Proportioning Valve
MAPManifold Absolute Pressure
MAX.Maximum
MICMicrophone
MILMalfunction Indicator Lamp
MIN.Minimum
MG1Motor Generator No.1
MG2Motor Generator No.2
MPMultipurpose
MPIMultipoint Electronic Injection
MPXMultiplex Communication System
M/T, MTMManual Transmission (Transaxle)
MTMount
MTGMounting
NNeutral
NANatural Aspiration
NO.Number
O2SOxygen Sensor
O/DOverdrive