ECU TOYOTA SEQUOIA 2017 2.G Workshop Manual

444 4-3. Do-it-yourself maintenance
15 ECU-IG No.1 7.5 AAnti-lock brake system, vehicle sta-
bility control system, multiplex com-
munication system, intuitive
parking assist system, power front
driver’s seat, power tilt and power
telescopic, shift lock, tire pressure
warning system, accessory meter,
trailer towing, power outlet, electric
moon roof, power back door, head
light cleaner, Blind Spot Monitor
system, BSM main switch
16 AIR SUS IG 20 A Electronically modulated air sus-
pension system
17 LH-IG 7.5 A Back-up lights, charging system,
gauge and meters, turn signal
lights, air conditioning system, seat
heaters, rear window defogger
18 4WD 20 A Four-wheel drive control system
19 RR SEAT-HTR
LH 10 A Seat heaters
20 WSH 20 A Window washer
21 WIPER 30 A Wiper and washer
22 ECU-IG No.2 7.5 A Multiplex communication system,
power steering, gateway ECU
23 TAIL 15 A Tail lights, trailer lights (tail lights),
parking lights
24 A/C IG 10 A Air conditioning system
25 SEAT-HTR 20 A Seat heater or Heated and venti-
lated seats
FuseAmpereCircuit

458 4-3. Do-it-yourself maintenance
CAUTION
■Replacing light bulbs
●Turn off the headlights. Do not attempt to replace the bulb immediately
after turning off the headlights.
The bulbs become very hot and may cause burns.
● Do not touch the glass portion of the light bulb with bare hands. When i\
t is
unavoidable to hold the glass portion, use and hold with a clean dry cloth
to avoid getting moisture and oils on the bulb.
Also, if the bulb is scratched or dropped, it may blow out or crack.
● Fully install light bulbs and any parts used to secure them. Failing to do so
may result in heat damage, fire, or water entering the headlight unit. This
may damage the headlights or cause condensation to build up on the lens.
■ To prevent damage or fire
Make sure bulbs are fully seated and locked.

5
When trouble arises
463
5-1. Essential information
Vehicles without electronica
lly modulated air suspension
If you use chains or cables to tie
down your vehicle, the angles
shaded in black must be 45 °.
Do not overly tighten the tie
downs or the vehicle may be
damaged.
Vehicles with electronically modulated air suspension
If you use chains or cables to tie
down your vehicle, the angles
shaded in black must be 45 °.
Do not overly tighten the tie
downs or the vehicle may be
damaged.
Emergency towing
If a tow truck is not available in an emergency, your vehicle may be
temporarily towed using cables or chains secured to the emergency
towing hooks. This should only atte mpted on hard, surfaced roads for
at most 50 miles (80 km) at under 18mph (30 km/h).
A driver must be in the vehicle to steer and operate the brakes. The
vehicle’s wheels, drive train, axles, steering and brakes must be in
good condition.

464 5-1. Essential information
Emergency towing procedureTYPE A Securely attach cables or chains
to the towing hooks.
Take care not to damage the
vehicle body.
TYPE BSecurely attach cables or chains
to the towing hooks.
Take care not to damage the
vehicle body.
Enter the vehicle being towed and start the engine.
If the engine does not start, turn the engine switch to the “ON”
position.
4WD models: Put the front-wh eel drive control switch in
“2WD”.
Shift the shift lever to N and release the parking brake.
When the shift lever cannot be shifted: ( →P. 499)
■While towing
If the engine is not running, the powe r assist for the brakes and steering
will not function, making steering and braking more difficult.

466 5-1. Essential information
NOTICE
■To prevent damage to the vehicle when towing using a wheel-lift
type truck
●Do not tow the vehicle from the rear when the engine switch is in the
LOCK position or the key is removed.
The steering lock mechanism is not strong enough to hold the front
wheels straight.
●When raising the vehicle, ensure adequate ground clearance for tow-
ing at the opposite end of the raised vehicle. Without adequate clear-
ance, the vehicle could be damaged while being towed.
■To prevent damage to the vehicle when towing with a sling-type
truck
Do not tow with a sling-type truck, either from the front or rear.
■To prevent damage to the vehicle during emergency towing
Do not secure cables or chains to the suspension components.

5
When trouble arises
475
5-2. Steps to take in an emergency
■
Four-wheel drive system warning buzzer
The buzzer indicated that the transfer mode is not selected correctly.
■ Key reminder buzzer
The buzzer indicates that the key has not been removed (with the engine
switch in the ACC or LOCK position and the driver’s door opened).
■ Open moon roof reminder buzzer
The buzzer indicate that the moon roof is still opened (with the engine switch
in the ACC or LOCK position and the driver’s door opened).
■ If the malfunction indicator lamp comes on while driving
First check the following:
● Is your vehicle low on gas?
If it is, refuel the vehicle immediately.
● Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after taking several driving trips.
If the light does not go off even after several trips, contact your Toyota dealer
as soon as possible.
■ Front passenger detection sensor and passenger seat belt reminder
If luggage or other load is placed on the front passenger seat, depending on
its weight, the reminder light to flash and buzzer to sound.
■
When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level.
Pushing the tire pressure warning reset switch does not turn off the tire
pressure warning light.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on due to natural causes such
as natural air leaks or tire inflat ion pressure changes caused by tem-
perature. In this case, adjusting the tire inflation pressure will turn off the
warning light (after several minutes).

5
When trouble arises
493
5-2. Steps to take in an emergency
Confirm that the tire is not loose
after tightening:
Push and pull the tire
Try rotating
Visually check to ensure the tire
is not hung on surrounding
parts.
If looseness or misassembly
exists, repeat step 2 and step 3.
Repeat step 3 any time the ti re is lowered or disturbed.
Stow the tools and jack securely.
■After completing the tire change
The tire pressure warning system must be reset. (→P. 417)
■When using the temporary spare tire
As the temporary spare tire is not equipped with the tire pressure warn-
ing valve and transmitter, low inflation pressure of the temporary spare
tire will not be warned. Also, if you replace the temporary spare tire after
the tire pressure warning light comes on, the light remains on.
CAUTION
■Using the jack
Improper use of the jack may lead to death or serious injuries due to the
vehicle suddenly falling off the jack.
●Do not use the jack for any purpose other than replacing tires or install-
ing and removing tire chains.
●Only use the jack that comes with this vehicle for replacing a flat tire.
Do not use it on other vehicles, an d do not use other jacks for replac-
ing tires on this vehicle.
●Always check that the jack is securely set to the jack point.
●Do not put any part of your body under the vehicle supported by a jack.
●Do not start or run the engine while your vehicle is supported by the
jack.
●Do not raise the vehicle while someone is in it.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a hei ght greater than that required to
replace the tire.
●Use a jack stand if it is necessary to get under the vehicle.
Take particular care when lowering the vehicle to ensure that no one
working on or near the vehicle will be injured.

494 5-2. Steps to take in an emergency
CAUTION
■Using the jack handle
Insert the square head securely until you hear a click to prevent the
extension parts from coming apart unexpectedly.
■Replacing a flat tire
Observe the following precautions to reduce the risk of death or serious
injury.
●Retighten the wheel nuts within 100 miles (160 km) of driving. Other-
wise, the nuts may loosen and the wheels may fall off, which could
cause a serious accident.
●Lower the spare tire completely to the ground before removing it from
under the vehicle.
●Do not try to remove the wheel ornament by hand. Take due care in
handling the ornament to avoid unexpected personal injury.
●Have the wheel nuts tightened with a torque wrench as soon as possi-
ble after changing wheels.
Steel wheel: 154 ft·lbf (209 N·m, 21.3 kgf·m)
Aluminum wheel: 97 ft·lbf (131 N·m, 13.4 kgf·m)
Failure to follow these precautions could cause the nuts to loosen and
the wheels may fall off, which could lead to an accident causing death
or serious injury.
●Do not attach a heavily damaged wheel ornament, as it may fly off the
wheel while the ve hicle is moving.
●Be sure to install the wheel nuts with the tapered end facing inward.
(→ P. 428)
■When using the temporary spare tire
●Remember that your temporary spare tire is specifically designed for
use with your vehicle. Do not use your temporary spare tire on another
vehicle.
●Do not use two temporary spare tires simultaneously.
●Replace the temporary spare tire with a standard tire as soon as possi-
ble.
●Avoid sudden acceleration, deceleration and braking, as well as sharp
cornering.

538 6-1. Specifications
*:Table 1 ⎯ Occupant loading and distribut ion for vehicle normal load
for various designate d seating capacities
Tire related termMeaning
TreadThat portion of a tire that comes into contact
with the road
Tread ribA tread section runnin g circumferentially
around a tire
Tread separationPulling away of the tread from the tire carcass
Treadwear indica-
tors(TWI)The projections within the principal grooves
designed to give a visual indication of the
degrees of wear of the tread
Wheel-holding fixtureThe fixture used to hold the wheel and tire
assembly securely during testing
Designated seating
capacity, Number of occupants Vehicle normal load,
Number of occupantsOccupant distribution in a normally loaded vehicle
2 through 422 in front
5 through 1032 in front, 1 in second seat
11 through 155
2 in front, 1 in second
seat, 1 in third seat, 1 in fourth seat
16 through 207
2 in front, 2 in second
seat, 2 in third seat, 1 in fourth seat

560
Abbreviation list
Abbreviation/Acronym list
ABBREVIATIONSMEANING
2WDTwo Wheel Drive
4WD Four Wheel Drive ABS Anti-Lock Brake System
ACC Accessory
AI-SHIFT Artificial Intelligence shifting ALR Automatic Locking Retractor
A-TRAC Active Traction Control
AUTO LSD Automatic Limited Slip Differential AVS Adaptive Variable Suspension System
BSM Blind Spot Monitor CRS Child Restraint System
ECU Electronic Control Unit
EDR Event Data Recorder ELR Emergency Locking RetractorFFV Flexible Fuel Vehicle
GAWR Gross Axle Weight Rating
GCWR Gross Combination Weight Rating GVWR Gross Vehicle Weight Rating I/M Emission inspection and maintenance
INFO Information
LATCH Lower Anchors and Tethers for Children LED Light Emitting Diode
LT Light truck
M + S Mud + Snow MMT Methylcyclopentadienyl Manganese Tricarbonyl
MTBE Methyl Tertiary Butyl Ether OBD On Board Diagnostics