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655
4-3. Do-it-yourself maintenance
4
Maintenance and care
GX460_CANADA (OM60F29U)
19ECU-IG NO.210 A
Rear window defogger, outside rear
view mirror memory, seat heater/ ven-
tilator switch, inverter relay, air condi-
tioning system, EC mirror, BODY
ECU, exhaust gas sensor, parking
assist sensor, navigation system,
DSS#2 ECU, meter switch, accessory
meter, folding seat ECU, O/H IG,
head light cleaner, rear air condition-
ing system, deicer, D-module, rain
sensor, air suspension, RR VLV ECU,
steering heater, LKA, P/SEAT IND
20S/HTR FR20 ASeat heater and ventilator
21P/ S E AT F R30 AFront power seat (right)
22DOOR P30 A
Front power window (passenger’s
side), outside rear view mirror mem-
ory
23DOOR10 APo w e r w i n d o w
24DOOR D25 AFront power window (driver’s side)
25DOOR RR25 ARear power window (right)
26S/ROOF25 AMoon roof
27WIP30 AWindshield wipers and washer
28WA S H E R20 AWindshield wipers and washer, rear
window wipers and washer
29COOLING10 ACool box
FuseAmpereCircuit
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656
4-3. Do-it-yourself maintenance
GX460_CANADA (OM60F29U)
30IGN10 A
EFI ECU, C/OPN RLY, VSC ECU, air
bag ECU, smart entry & start system,
steering lock ECU, CAN gateway
ECU
31GAUGE7. 5 AMeter
32PA N E L7. 5 A
Switch illumination, glove box light,
navigation system, audio system, air
conditioning system, outside rear view
mirror switch, folding seat switch,
multi-information display, P/SEAT
IND, SHIFT, COOL BOX
33TA I L10 A
Front position lights, tail lights, license
plate lights, EFI ECU, rear fog lights,
towing, front fog lights
FuseAmpereCircuit
GX460_CANADA.book Page 656 Thursday, February 4, 2010 11:54 AM
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5
When trouble arises
679
5-1. Essential information
GX460_CANADA (OM60F29U)
■Before emergency towingThe “ENGINE START STOP” switch must be in the ACCESSORY mode
(engine off) or IGNITION ON mode (engine running).
Put the four-wheel drive control switch in H4. (The center differential is
unlocked.)
Put the vehicle height in the N mode and press height control switch to
turn off the rear height control air suspension.
Shift the shift lever in N.
Release the parking brake.
CAUTION
■Caution while towing
●Use extreme caution when towing the vehicle.
Avoid sudden starts or erratic driving maneuvers which place excessive stress on
the emergency towing eyelets and the cables or chains. Always use caution for
the surroundings and other vehicles while towing.
●Do not turn the “ENGINE START STOP” switch off.
Doing so will lock the steering wheel an d prevent operation, possibly causing an
accident and resulting in death or serious injury.
●If the engine is not running, the power assist for the brakes and steering will not
function, making steering and braking more difficult.
STEP1
STEP2
STEP3
STEP4
STEP5
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5
When trouble arises
695
5-2. Steps to take in an emergency
GX460_CANADA (OM60F29U)
CAUTION
■If both the ABS and the brake system warning lights remain on
Stop your vehicle in a safe place immediately and contact your Lexus dealer. The
vehicle will become extremely unstable during braking, and the ABS system may
fail, which could cause an accident resulting in death or serious injury.
■When the power steering system warning light comes on
The steering wheel may become extremely heavy.
If the steering wheel becomes heavier than usual when operating, hold firmly and
operate using more force than usual.
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could cause loss of
vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as soon as possible. Adjust the tire inflation pres-
sure immediately.
●If the tire pressure warning light comes on even after tire inflation pressure adjust-
ment, it is probable that you have a flat tire. Check the tires. If the tire is flat,
change to the spare tire and have the flat tire repaired by the nearest Lexus
dealer.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate, you could
lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning system may not activate immediately.
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Page 701 of 830
700
5-2. Steps to take in an emergency
GX460_CANADA (OM60F29U)
Have the vehicle inspected by your Lexus dealer immediately.A buzzer sounds and a warning message is shown on the multi-informa-
tion display. Failure to investigate the cause of the following warnings may
lead to the system operating abnormally and possibly cause an accident.
Have the vehicle inspected by your Lexus dealer immediately.
Wa r n i n g m e s s a g eDetails
Indicates that the automatic transmission fluid tem-
perature is too high
Indicates a malfunction in the automatic transmission
system
Indicates a malfunction in the steering lock system
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Page 719 of 830
718
5-2. Steps to take in an emergency
GX460_CANADA (OM60F29U)
Sounds
once
(Flashes)
The steering lock
could not be
released within 3
seconds of the
“ENGINE START
STOP” switch
being pressed.
Press the
“ENGINE START
STOP” switch
while depressing
the brake pedal
and moving the
steering wheel left
and right.
InteriorbuzzerExterior buzzerWarning messageDetailsCorrection
procedure
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5
When trouble arises
735
5-2. Steps to take in an emergency
GX460_CANADA (OM60F29U)
Emergency start function
When the engine does not start, the following steps can be used as an
interim measure to start the engine if the “ENGINE START STOP” switch
is functioning normally:Set the parking brake.
Shift the shift lever to P.
Turn the “ENGINE START STOP” switch to ACCESSORY
mode.
Press and hold the “ENGINE START STOP” switch for about 15
seconds while depressing the brake pedal firmly.
Even if the engine can be started using the above steps, the system may
be malfunctioning. Have the vehicle inspected by your Lexus dealer.
■ The starter motor does not turn ov er, interior lights and headlights
do not turn on, or the horn does not sound
One of the following may be the cause of the problem:
● One or both of the battery terminals may be disconnected.
● The battery may be discharged. ( →P. 74 1 )
● There may be a malfunction in the steering lock system.
Contact your Lexus dealer if the problem cannot be repaired, or if
repair procedures are unknown.
STEP1
STEP2
STEP3
STEP4
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750
5-2. Steps to take in an emergency
GX460_CANADA (OM60F29U)
CAUTION
■If the engine has to be turned off while driving
Power assist for the brakes and steering wheel will be lost, making the brake pedal
harder to depress and the steering wheel heavier to turn. Decelerate as much as
possible before turning off the engine.
GX460_CANADA.book Page 750 Thursday, February 4, 2010 11:54 AM