2001 TOYOTA SEQUOIA connectors

FI1066
IN0D9±03
Z11554
Seal Lock Adhesive IN±4
± INTRODUCTIONREPAIR INSTRUCTIONS
4 Author: Date:
2005 SEQUOIA (RM1146U)
REPAIR INSTRUCTIONS
GENERAL INFORMATION
BASIC REPAIR HINT
(a) Prevent damage and maintain vehicle cleanliness by pro-
tective covering on the fender, seat and floor.
(b) During disassembly, keep parts in the appropriate order
to facilitate reassembly.
(c) Installation and removal of battery terminal:
(1) Before performing electrical work, disconnect the
negative (±) terminal cable from the battery.
(2) If it is necessary to disconnect the battery for in-
spection or repair, first disconnect the negative (±)
terminal cable.
(3) When disconnecting the terminal cable, to prevent
damage to battery terminal, loosen the cable nut
and raise the cable straight up without twisting or
prying it.
(4) Clean the battery terminals and cable ends with a
clean shop rag. Do not scrape them with a file or oth-
er abrasive objects.
(5) Install the cable ends to the battery terminals after
loosening the nut and tighten the nut. Do not use a
hammer to tap the cable ends onto the terminals.
(6) Be sure the cover for the positive (+) terminal is
properly in place.
(d) Check hose and wiring connectors to make sure that they
are connected securely and correctly.
(e) Non±reusable parts
(1) Always replace cotter pins, gaskets, O±rings, oil
seals, etc. with new ones.
(2) Non±reusable parts are indicated in the component
illustrations by the ºº symbol.
(f) Precoated parts
Precoated parts are bolts, nuts, etc. that are coated with
a seal lock adhesive at the factory.
(1) If a precoated part is retightened, loosened or
caused to move in any way, it must be recoated with
the specified adhesive.
(2) When reusing precoated parts, clean off the old
adhesive and dry with compressed air. Then apply
the specified seal lock adhesive to the bolt, nut or
threads.

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.

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.

V07268
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
WIRE HARNESS
PARTS AND SENSOR1
Slightly shake the connector vertically and horizontally.
Slightly shake the wire harness vertically and horizontally.
The connector joint, fulcrum of the vibration, and body
through portion are the major areas to be checked thorough-
ly.
Apply slight vibration with a finger to the part of the sensor
considered to be the problem cause and check that the mal-
function occurs.Shake Slightly
Swing Slightly
Vibrate Slightly
HINT:
Applying strong vibration to relays may result in open relays.
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±29
29 Author: Date:
2005 SEQUOIA (RM1146U)
3. SYMPTOM SIMULATION
The most difficult case in troubleshooting is when there are no problem symptoms occurring. In such cases,
a thorough customer problem analysis must be carried out, then simulate the same or similar conditions and
environment in which the problem occurred in the customer's vehicle. No matter how much experience a
technician has, or how skilled he may be, if he proceeds to troubleshoot without confirming the problem
symptoms he will tend to overlook something important in the repair operation and make a wrong guess
somewhere, which will only lead to a standstill. For example, for a problem which only occurs when the en-
gine is cold, or for a problem which occurs due to vibration caused by the road during driving, etc., the prob-
lem can never be determined so long as the symptoms are confirmed with the engine hot or the vehicle at
a standstill. Since vibration, heat or water penetration (moisture) is likely cause for problem which is difficult
to reproduce, the symptom simulation tests introduced here are effective measures in that the external
causes are applied to the vehicle in a stopped condition.
Important Points in the Symptom Simulation Test:
In the symptom simulation test, the problem symptoms should be confirmed, but the problem area or parts
must also be found out. To do this, narrow down the possible problem circuits according to the symptoms
before starting this test and connect a tester beforehand. After that, carry out the symptom simulation test,
judging whether the circuit being tested is defective or normal and also confirming the problem symptoms
at the same time. Refer to the problem symptoms table for each system to narrow down the possible causes
of the symptom.

FI0048
FI0047
FI0046
IN011±61
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±35
35 Author: Date:
2005 SEQUOIA (RM1146U)
HOW TO USE THE DIAGNOSTIC
CHART AND INSPECTION
PROCEDURE
1. CONNECTOR CONNECTION AND TERMINAL IN-
SPECTION

For troubleshooting, diagnostic trouble code charts or
problem symptom table are provided for each circuit with
detailed inspection procedures on the following pages.

When all the component parts, wire harnesses and con-
nectors of each circuit except the ECU are found to be
normal in troubleshooting, then it is determined that the
problem is in the ECU. Accordingly, if diagnosis is per-
formed without the problem symptoms occurring, refer to
step 8 to replace the ECU. So always confirm that the
problem symptoms are occurring, or proceed with inspec-
tion while using the symptom simulation method.

The instructions ºCheck wire harness and connectorº and
ºCheck and replace ECUº which appear in the inspection
procedure, are common and applicable to all diagnostic
trouble codes. Follow the procedure outlined below
whenever these instructions appear.
OPEN CIRCUIT:
This could be due to a disconnected wire harness, faulty con-
tact in the connector, and a connector terminal pulled out, etc.
HINT:

It is rarely the case that a wire is broken in the middle of
it. Most cases occur at the connector. In particular, care-
fully check the connectors of sensors and actuators.

Faulty contact could be due to rusting of the connector
terminals, to foreign materials entering terminals or a de-
formation of connector terminals. Simply disconnecting
and reconnecting the connectors once changes the
condition of the connection and may result in a return to
normal operation. Therefore, in troubleshooting, if no ab-
normality is found in the wire harness and connector
check, but the problem disappears after the check, then
the cause is considered to be in the wire harness or con-
nectors.
SHORT CIRCUIT:
This could be due to a contact between wire harness and the
body ground or to a short circuit occurred inside the switch, etc.
HINT:
When there is a short circuit between the wire harness and body
ground, check thoroughly whether the wire harness is caught
in the body or is clamped properly.

FI7187
IN0379
Sensor Side
ECU Side
IN0378
Sensor SideECU Side
IN0380
Sensor SideECU Side
IN0381
Pull Lightly
Looseness of Crimping
IN±36± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
36 Author: Date:
2005 SEQUOIA (RM1146U)
2. CONNECTOR HANDLING
When inserting tester probes into a connector, insert them from
the rear of the connector. When necessary, use mini test leads.
For water resistant connectors which cannot be accessed from
behind, take good care not to deform the connector terminals.
3. CONTINUITY CHECK (OPEN CIRCUIT CHECK)
(a) Disconnect the connectors at both ECU and sensor
sides.
(b) Measure the resistance between the applicable terminals
of the connectors.
Resistance: 1 W or less
HINT:
Measure the resistance while lightly shaking the wire harness
vertically and horizontally.
4. RESISTANCE CHECK (SHORT CIRCUIT CHECK)
(a) Disconnect the connectors on both ends.
(b) Measure the resistance between the applicable terminals
of the connectors and body ground. Be sure to carry out
this check on the connectors on both ends.
Resistance: 1 MW or higher
HINT:
Measure the resistance while lightly shaking the wire harness
vertically and horizontally.
5. VISUAL CHECK AND CONTACT PRESSURE CHECK
(a) Disconnect the connectors at both ends.
(b) Check for rust or foreign material, etc. in the terminals of
the connectors.
(c) Check crimped portions for looseness or damage and
check that the terminals are secured in lock portion.
HINT:
The terminals should not come out when pulled lightly from the
back.

Z17004
Fig. 1
OPENECU
2 Sensor
22 21 111A B C
Z17005
Fig. 2
ECU
Sensor
21A
B C
1
1
22
B04722
Fig. 3
ECU
Sensor
21A
B1
C
1
1
221
2 B2
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN±37
37 Author: Date:
2005 SEQUOIA (RM1146U)
(d) Prepare a test male terminal and insert it in the female ter-
minal, then pull it out.
NOTICE:
When testing a gold±plated female terminal, always use a
gold±plated male terminal.
HINT:
When the test terminal is pulled out more easily than others,
there may be poor contact in that section.
6. CHECK OPEN CIRCUIT
For an open circuit in the wire harness in Fig. 1, perform º(a)
Continuity Checkº or º(b) Voltage Checkº to locate the section.
(a) Check the continuity.
(1) Disconnect connectors ºAº and ºCº and measure
the resistance between them.
In the case of Fig. 2:
Between terminal 1 of connector ºAº and terminal 1
of connector ºCº " No continuity (open)
Between terminal 2 of connector ºAº and terminal 2
of connector ºCº " Continuity
Therefore, it is found out that there is an open circuit
between terminal 1 of connector ºAº and terminal 1
of connector ºCº.
(2) Disconnect connector ºBº and measure the resis-
tance between the connectors.
In the case of Fig. 3:
Between terminal 1 of connector ºAº and terminal 1
of connector ºB1º " Continuity
Between terminal 1 of connector ºB2º and terminal
1 of connector ºCº " No continuity (open)
Therefore, it is found out that there is an open circuit
between terminal 1 of connector ºB2º and terminal
1 of connector ºCº.

Z17007
Fig. 4
Sensor
21A
C
1
1
22B5V
5V
5V
0V
Z17008
Fig. 5
2 1A C
1
1
22
BSHORT
Z17009
Fig. 6
21A C
1
1
22
BSensorECU IN±38
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
38 Author: Date:
2005 SEQUOIA (RM1146U)
(b) Check the voltage.
In a circuit in which voltage is applied (to the ECU connec-
tor terminal), an open circuit can be checked by conduct-
ing a voltage check.
As shown in Fig. 4, with each connector still con-
nected, measure the voltage between body ground
and terminal 1 of connector ºAº at the ECU 5V out-
put terminal, terminal 1 of connector ºBº, and termi-
nal 1 of connector ºCº, in that order.
If the results are:
5V: Between Terminal 1 of connector ºAº and Body Ground
5V: Between Terminal 1 of connector ºBº and Body Ground
0V: Between Terminal 1 of connector ºCº and Body Ground
Then it is found out that there is an open circuit in the wire har-
ness between terminal 1 of ºBº and terminal 1 of ºCº.
7. CHECK SHORT CIRCUIT
If the wire harness is shorted as in Fig. 5, locate the section by
conducting a ºcontinuity check with groundº.
Check the continuity with ground.
(1) Disconnect connectors ºAº and ºCº and measure
the resistance between terminals 1 and 2 of con-
nector ºAº and body ground.
In the case of Fig. 6:
Between terminal 1 of connector ºAº and body
ground " Continuity (short)
Between terminal 2 of connector ºAº and body
ground " No continuity
Therefore, it is found out that there is a short circuit
between terminal 1 of connector ºAº and terminal 1
of connector ºCº.