engine overheat Lexus GX460 2012 User Guide

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2-4. Using other driving systems
2
When driving
GX460_U.S.A. (OM60J00U)
■Operating tips
The system will operate when the shift lever is in a position other than P, however to
make effective use of the system it is recommended that the shift lever be shifted to
2 or 1 range of S mode.
■If the four-wheel drive control switch is in H4
The system does not operate.
■When the downhill assist control system is operated continuously
This may cause the brake actuator to overheat. In this case, the downhill assist con-
trol system will stop operating, a buzzer will sound and the DAC indicator will start
flashing, and the TRAC OFF will be shown on the multi-information display. Refrain
from using the system until the DAC indicator stays on and the message goes off.
(The vehicle can be driven normally during this time.)
■Sounds and vibrations caused by the DAC
●A sound may be heard from the engine compartment when the engine is
started or just after the vehicle begins to move. This sound does not indicate that
a malfunction has occurred in DAC.
●Either of the following conditions may occur when the DAC is operating. None
of these are indicators that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
■System malfunction
●The DAC indicator does not come on when the “ENGINE START STOP”
switch is turned to IGNITION ON mode.
●The “DAC” indicator does not come on when the “DAC” switch is pressed.
●The slip indicator comes on.
In the above cases, have your vehicle checked by your Lexus dealer.

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2-5. Driving information
GX460_U.S.A. (OM60J00U)●
Avoid jerky starts or sudden acceleration.
● Avoid jerky steering and sharp turns, and slow down before making a
turn.
● Note that when making a turn, the trailer wheels will be closer than the
vehicle wheels to the inside of the turn. Compensate by making a
wider than normal turning radius.
● Slow down before making a turn, in crosswinds, on wet or slippery sur-
faces, etc.
Increasing vehicle speed can destabilize the trailer.
● Take care when passing other vehicles. Passing requires considerable
distance. After passing a vehicle, do not forget the length of your
trailer, and be sure you have plenty of room before changing lanes.
● To maintain engine braking efficiency and charging system perfor-
mance when using engine braking, do not put the transmission in D.
Transmission shift range position must be in 5 in the S mode.
● Instability happens more frequently when descending steep or long
downhill grades. Before descending, slow down and downshift. Do not
make sudden downshifts while descending steep or long downhill
grades.
● Avoid holding the brake pedal down too long or applying the brakes
too frequently. This could cause the brakes to overheat and result in
reduced braking efficiency.
● Due to the added load of the trailer, your vehicle’s engine may overheat
on hot days (at temperatures over 85°F [30°C]) when driving up a
long or steep grade. If the engine coolant temperature gauge indicates
overheating, immediately turn off the air conditioning (if in use), pull
your vehicle off the road and stop in a safe spot. ( →P. 744)

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3-7. Other interior features
3
Interior features
GX460_U.S.A. (OM60J00U)
CAUTION
■Burns
●Use caution when seating the following persons in a seat with the seat heater on
to avoid the possibility of burns:
• Babies, small children, the elderly, the sick and the physically challenged
• Persons with sensitive skin
• Persons who are fatigued
• Persons who have taken alcohol or drugs that induce sleep (sleeping drugs,cold remedies, etc.)
●Do not cover the seat with anything when using the seat heater.
Using the seat heater with a blanket or cushion increases the temperature of the
seat and may lead to overheating.
●Do not use the seat heater more than necessary. Doing so may cause minor
burns or overheating.
NOTICE
■To prevent damage to the seat heaters and ventilators
Do not put heavy objects that have an uneven surface on the seat and do not stick
sharp objects (needles, nails, etc.) into the seat.
■To prevent battery discharge
Turn the seat heaters and ventilators off when the engine is not running.

When trouble arises5
675
GX460_U.S.A. (OM60J00U)
5-1. Essential informationEmergency flashers................ 676
If your vehicle needs to be towed ............................ 677
If you think something is wrong ..................................... 683
Fuel pump shut off system.... 684
Event data recorder .............. 685 5-2. Steps to take in an
emergency
If a warning light turns on or a warning buzzer
sounds..................................... 688
If a warning message is displayed................................ 700
If you have a flat tire................. 721
If the engine will not start .... 735
If the shift lever cannot be shifted from P ........................ 737
If you lose your keys .............. 738
If the electronic key does not operate properly.......... 739
If the vehicle battery is discharged .............................. 741
If your vehicle overheats ...... 744
If the vehicle becomes stuck......................................... 747
If your vehicle has to be stopped in an emergency ................... 749

744
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60J00U)
If your vehicle overheats
If the engine overheats:
Stop the vehicle in a safe place and turn off the automatic air
conditioning system.
Check to see if steam is coming out from under the hood.
If you see steam: Stop the engine. Carefully lift the hood after the steam sub-
sides and then restart the engine.
If you do not see steam: Leave the engine running and carefully lift the hood.
Check to see if the cooling fan is operating.
If the fan is operating: Wait until the engine coolant temperature gauge begins to
fall and then stop the engine.
If the fan is not operating: Stop the engine and call your local Lexus dealer.STEP1
STEP2
STEP3

746
5-2. Steps to take in an emergency
GX460_U.S.A. (OM60J00U)
■Overheating
In the following situations, your vehicle may be overheating:
●The engine coolant temperature gauge enters the red zone or a loss of power is
experienced.
●Steam is coming from under the hood.
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartment may be very hot, causing serious
injury such as burns.
●Keep hands and clothing away from the fan and engine drive belt while the
engine is running.
●Do not loosen the radiator cap while the engine and radiator are hot.
Serious injury, such as burns, may result from hot coolant and steam released
under pressure.
NOTICE
■When adding engine coolant
Wait until the engine has cooled down before adding coolant.
When adding coolant, do so slowly. Adding cold coolant to a hot engine too quickly
can cause damage to the engine.

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Alphabetical index
GX460_U.S.A. (OM60J00U)
Child-protectors ....................................... 51
CleaningExterior .................................................. 588
Interior .....................................................593
Seat belts................................................594
Clock
*..................................................... 540
Coat hooks ............................................. 555
Coin holder .............................................528
Compass .................................................. 575
Condenser ............................................... 618
Console box ...........................................526
Conversation mirror ............................ 541
Cool box...................................................535
Cooling system Engine overheating .......................... 744
Cornering assist sensors ................... 266
Crawl Control........................................328
Cruise control
Cruise control ..................................... 246
Dynamic radar cruise control .....250
Cup holders ........................................... 530
Curtain shield airbags.......................... 122
Customizable features .......................782
Daytime running light system .......... 224
DAC...........................................................332
Defogger Rear window............................................411
Side mirror ................................................411
Dimension ................................................ 752
Dinghy towing ....................................... 389 Display
Dynamic radar cruise control..... 250
Multi-information display........................................ 204, 212
Trip information........................ 204, 212
Warning message ............................ 700
Do-it-yourself maintenance ............. 603
Door courtesy lights Door courtesy lights .......................... 519
Wattage ..................................................763
Door pocket ........................................... 529
Doors Back door .................................................53
Power windows .....................................101
Door lock .........................................47, 50
Rear door child protector.................. 51
Side doors................................................ 50
Side mirrors.............................................. 97
Downhill assist control system ........ 332
Driver’s seat belt reminder light ..... 692
Driving Correct posture................................... 120
Off-road precautions...................... 353
Procedures............................................. 168
Winter driving tips ............................ 366
Driving position memory...................... 78
D

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Alphabetical index
GX460_U.S.A. (OM60J00U)
Electronic keyIf the electronic key does not
operate properly ............................ 739
Emergency, in case of
If the electronic key does not operate properly ............................ 739
If the engine will not start ............... 735
If the shift lever cannot be shifted from P.................................... 737
If the vehicle has discharged
battery.................................................... 741
If the warning buzzer sounds..... 688
If the warning light turns on ......... 688
If the warning message is
displayed ............................................ 700
If you have a flat tire .......................... 721
If you lose your keys ........................ 738
If you think something is
wrong...................................................683
If your vehicle becomes stuck .....747
If your vehicle has to be stopped in an emergency ......... 749
If your vehicle needs to be towed ....................................................677
If your vehicle overheats.................744
Emergency flashers
Switch ...................................................... 676 Engine
Accessory mode..................................179
Compartment..................................... 609
Engine switch .........................................179
Hood ....................................................... 608
How to start the engine ....................179
Identification number .......................753
If the engine will not start................735
Ignition switch ........................................179
Overheating ......................................... 744
Engine compartment cover .............. 610
Engine coolant Capacity ................................................. 757
Checking ................................................ 616
Preparing and checking before winter ................................... 366
Engine coolant temperature gauge....................................................... 195
Engine immobilizer system..................115
Engine oil Capacity .................................................755
Checking .................................................. 611
Preparing and checking before winter ................................... 366
Engine oil maintenance data............. 613
Engine switch ...........................................179
Engine switch light................................. 519
Event data recorder ........................... 685E
*: For vehicles with a navigation system, refer to the “Navigation System Owner’s Manual”.

826
Alphabetical index
GX460_U.S.A. (OM60J00U)
LightsDoor courtesy lights.......................... 519
Emergency flasher switch ............. 676
Engine switch light ............................. 519
Fog light switch................................... 233
Hazard light switch ........................... 676
Headlights switch ................................ 219
Inside door handle light................... 519
Interior lights list................................... 519
Personal/interior lights .....................521
Replacing light bulbs........................ 662
Running board lights......................... 519
Scuff lights............................................... 519
Shift lever light ...................................... 519
Turn signal lever ................................... 192
Vanity lights ..........................................539
Wattage.................................................. 763
Load capacity .........................................364
Luggage cover...................................... 560
Maintenance Do-it-yourself ma intenance .........603
General maintenance .................... 598
Maintenance data.............................. 752
Maintenance requirements ..........596
Meter
Instrument cluster light control....................................................196
Meters ...................................................... 195
Micro dust and pollen filter................ 401
Mirrors Inside rear view mirror....................... 95
Side mirror heater .................................411
Side mirrors ............................................. 97
Vanity mirrors......................................539 Moon roof................................................. 104
MP3 disc....................................................431
Multi-information display
Brightness control .............................. 215
Multi-information display ........ 204, 212
Multi Terrain ABS ................................ 335
Multi-terrain Monitor ......................... 304
Multi-terrain Select.............................. 296
Navigation system
*
Noise from under vehicle .................... 20
Odometer ................................................ 195
Off-road precautions ......................... 353
Oil Engine oil................................................... 611
Opener Fuel filler door .......................................109
Hood .......................................................608
Outside rear view mirrors
Adjusting and folding .......................... 97
Driving position memory ..................78
Outside temperature display .......................................... 205, 212
Overhead console ............................... 533
Overheating, Engine .......................... 744
Parking assist sensors......................... 266
Parking brake...........................................193
Parking lights Replacing light bulbs ....................... 667
Switch ........................................................ 219
Wattage ..................................................763
PCS ............................................................ 343
M
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GX460_U.S.A. (OM60J00U)
What to do if...
What to do if...
A tire puncturesP. 7 2 1If you have a flat tire
The engine does not start
P. 1 1 5Engine immobilizer system
P. 7 3 5If the engine will not start
P. 74 1If the vehicle battery is discharged
The shift lever cannot be
moved outP. 7 3 7If the shift lever cannot be shifted
from “P”
The engine coolant temperature
gauge enters the red zone
Steam can be seen coming
from under the hood
P. 74 4If your vehicle overheats
The key is lostP. 7 3 8If you lose your keys
The battery is dischargedP. 74 1If the vehicle battery is discharged
The doors cannot be lockedP. 5 0Side doors
P. 5 3Back door
The horn begins to soundP. 1 1 7Alarm
The vehicle is stuck in mud or
sandP. 74 7If the vehicle becomes stuck