check engine Lexus GX460 2021 / Service Manual

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GX460_OM_OM60T19U_(U)6-3. Do-it-yourself maintenance
Checking and replacing fuses
Turn the engine switch off.
Open the fuse box cover.
Remove the fuse with the pull-out tool.
Only type A fuse can be removed using
the pull-out tool.
If any of the electrical components do not operate, a fuse may have blown. If
this happens, check and repl ace the fuses as necessary.
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Engine compartmentDriver’s side instrument panel
Push the tab in and lift the lid off. Remove the lid.
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5227-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
*1: This light illuminates on the multi-information display.
*2: Open door warning buzzer: The open door warning buzzer sounds to al ert hood or one or more of the doors or
glass hatch are not fully closed (with the vehicle having reached a speed of 3 mph [5
km/h]).
*3: Driver’s seat belt warning buzzer:
The driver’s seat belt warning buzzer sounds to alert the driver that his or her seat belt
is not fastened. Once the engine switch is turned to ON, the buzzer sounds. If the seat
belt is still unfastened, the buzzer sounds intermittently for a certain period of time
after the vehicle reaches a certain speed.
Front passenger’s seat belt warning buzzer:
The front passenger’s seat belt warning buzzer sounds to alert the front passenger
that his or her seat belt is not fastened. If the seat belt is unfastened, the buzzer sounds
intermittently for a certain period of time after the vehicle reaches a certain speed.
■SRS warning light
This warning light system monitors the airbag sensor assembly, front airbag sensors, side
and curtain shield airbag sensors, rear side and curtain shield airbag sensors, floor sen-
sor, driver’s seat belt buc kle switch, front passenger occupant classification system (ECU
and sensors), “AIR BAG ON” indicator light, “AIR BAG OFF” indicator light, front pas-
senger’s seat belt buckle sw itch, seat belt pretensioner assemblies, airbags, intercon-
necting wiring and power sources. ( P. 36)
■Front passenger detection sensor, seat belt reminder and warning buzzer
●If luggage is placed on the front passenger seat, the front passenger detection sensor
may cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sittin g in the seat.
●If a cushion is placed on the seat, the sens or may not detect a passenger, and the warn-
ing light may not operate properly.
■If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fu el tank immediately.
●Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after severa l trips, contact your Lexus dealer as soon as
possible.

5237-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
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When trouble arises
■If the low speed four-wheel driv e indicator light or the center differential lock indicator
light blinks
Take the specified steps. ( P. 346)
■When the tire pressure warning light comes on
Inspect the tires to check if a tire is punctured.
If a tire is punctured:  P. 531
If none of the tires are punctured:
Turn the engine switch off then turn it to IGNITION ON mode. Check if the tire pressure
warning light comes on or flashes.
If the tire pressure warning light comes on
After the temperature of the tires has lowere d sufficiently, check the inflation pressure
of each tire and adjust th em to the specified level.
If the warning light does not turn off even after several minutes have elapsed, check
that the inflation pressure of each tire is at the specified level and perform initialization.
(  P. 474)
If the warning light does not turn off even after several minutes have elapsed, have the
vehicle inspected by your Lexus dealer immediately.
If the tire pressure wa rning light flashes for 1 minute then stay on
There may be a malfunction in the tire pressure warning system. Have the vehicle
inspected by your Lexus dealer immediately.
■The tire pressure warning light may turn on due to natural causes
The tire pressure warning light may turn on du e to natural causes such as natural air leaks
or tire inflation pressure changes caused by temperature. In this case, adjusting the tire
inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with a spare tire
The tire pressure warning light wi ll turn on if the tire inflation pressure of the spare tire is
low. If a tire goes flat, the tire pressure warn ing light will not turn off even though the flat
tire has been replaced with the spare tire.
■Conditions that the tire pressure wa rning system may not function properly
 P. 478
■If the tire pressure warning light freque ntly comes on after blinking for 1 minute
If the tire pressure warning light frequently comes on after blinking for 1 minute when the
engine switch is turned to IGNITION ON mo de, have it checked by your Lexus dealer.
■Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location or audio
sound.
■Customization
The vehicle speed linked seat belt reminder buzzer can be disabled.
(Customizable features: P. 584)
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5287-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
■Warning messages
The warning messages explained below may differ from the actual messages according
to operation conditions an d vehicle specifications.
■Warning buzzer
In some cases, the buzzer ma y not be heard due to being in a noisy location or audio
sound.
■If “ENGINE OIL LOW”/“Engine Oil Level Low Add or Replace” is shown
The engine oil level is low. Check the level of the engine oil, and add if necessary.
This message may appear if the vehicle is stopped on a slope. Move the vehicle to a level
surface and check to see if the message disappears.
■If “AUTO POWER OFF TO CONSERVE BATTE RY”/“Auto power off to conserve bat-
tery” is shown
Power was turned off due to the automatic power off function. Next time when starting
the engine, increase the engine speed slightly and maintain that level for approximately 5
minutes to recharge the battery.
■If “ENGINE OIL PRES SURE LOW”/“Oil Pressure Low Stop in a Safe Place See
Owner’s Manual” is shown
Indicates abnormal engine oil pressure.
Immediately stop the vehicle in a safe place and contact your Lexus dealer. Continuing to
drive the vehicle may be dangerous.
■If “HIGH TRANSMISSION FLUID TEMPERAT URE”/“High Transmission Fluid Temp
See Owner’s Manual” is shown.
It indicates that the automatic transmission fluid temperature is too high.
Immediately stop the vehicle in a safe place, shift the shift lever to P and wait until the
warning message disappear. If the warning message disappears, you may start the vehi-
cle again. If the warning message does not disappear, contact your Lexus dealer.
■If “Check Transmissi on System” is shown.
The automatic transmission system is malfunctioning.
Have the vehicle inspected by your Lexus dealer.
■If “ACCELERATOR AND BRAKE PEDA LS DEPRESSED SIMULTANEOUSLY”/
“Accelerator and Brake Pedals Pressed Simultaneously” is shown on the multi-informa-
tion display
The accelerator and brake pedal are being depressed simultaneously. ( P. 169)
Release the accelerator pedal and depress the brake pedal.
■If “HEADLIGHT SYSTEM MALFUNCTION VISIT YOUR DEALER”/“Headlight Sys-
tem Malfunction Visit Your Dealer” is displayed
The following systems may be malfunctioning. Have the vehicle inspected by your Lexus
dealer immediately.
●The LED headlight system
●The automatic headlight leveling system
●Automatic High Beam

5297-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
7
When trouble arises
■If a message that indica tes the malfunction of front camera is displayed
The following systems may be suspended until the problem shown in the message is
resolved. ( P. 238, 518)
●PCS (Pre-Collision System)
●LDA (Lane Departure Alert)
●Automatic High Beam
●Dynamic radar cruise control
■If “Radar Cruise Control Unavailable” is shown
The dynamic radar cruise control sy stem cannot be used temporarily.
Use the system when it becomes available again.
■If “Maintenance Required Soon” is shown (U.S.A. only)
Indicates that all maintenance according to the driven distance on the maintenance
schedule
* should be performed s oon. Comes on approximatel y 4500 miles (7200 km)
after the message has been reset. If necessary, perform main tenance. Please reset the
message after the maintenance is performed. ( P. 449)
*: Refer to the separate “Scheduled Maintena nce” or “Owner’s Manual Supplement” for
the maintenance interval applicable to your vehicle.
■If “Maintenance Required Visit Your Dealer” is shown (U.S.A. only)
Indicates that all maintenance is required to correspond to the driven distance on the
maintenance schedule
*.
Comes on approximately 5000 miles (8000 km) after the message has been reset.
(The indicator will not work properly unless the message has been reset.) Perform the
necessary maintenance. Please reset the message after the maintenance is performed.
(  P. 449)
*: Refer to the separate “Scheduled Maintena nce” or “Owner’s Manual Supplement” for
the maintenance interval applicable to your vehicle.
■If “Oil Maintenance Required Soon” is shown
Indicates that the engine oil should be scheduled to be changed.
Check the engine oil and change it if necessa ry. After changing the engine oil, make sure
to reset the message. ( P. 462)
■If “OIL MAINTENANCE REQU IRED” “Oil Maintenance Required Visit Your Dealer”
is shown
Indicates that the engine oil should be scheduled to be changed.
Check and change the engine o il, and oil filter by your Lexus dealer. After changing the
engine oil, make sure to reset the message. ( P. 462)
■If “Check Access System with Elec. Key” is shown
The smart access system with push-button star t may be malfunctioning. Have the vehicle
inspected by your Lexus dealer immediately.

5307-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
■If “SEE OWNER’S MANUAL”/“See Owner’s Manual” is shown
●If any of the following messages are shown on the multi-information display, follow the
instructions.
• “Engine Coolant Temp High” ( P. 553)
●If any of the following messages are shown on the multi-information display, it may indi-
cate a malfunction. Immediately stop the vehicle and contact your Lexus dealer.
• “BRAKING POWER LOW”/“Braking Power Low”
• “Charging System Malfunction”
■If a following message is shown, take appropriate action and confirm that the message
has disappeared. ( P. 348) (if equipped)
●“CRAWL NOT AVAILABLE SELECT L4 AND SHIFT TO D OR R POSITION”/
“Crawl Not Available Select L4 and Shift to D or R Position”
●“CRAWL NOT AVAILABLE CHECK SYSTEM OPERATION CONDITIONS”/
“Crawl Not Available Check System Operation Conditions”
■If “VISIT YOUR DEALER”/“Visit Your Dealer” or “CHECKED BY A DEALER”/
“checked by a dealer” is shown
The system or part shown on the multi-info rmation display is malfunctioning. Have the
vehicle inspected by your Lexus dealer immediately.

5337-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
7
When trouble arises
WARNING
■Using the tire jack
Improper use of the tire jack may cause the ve hicle to suddenly fall off the jack, leading
to death or serious injury.
●Do not use the tire jack for any purpose ot her than replacing tires or installing and
removing tire chains.
●Only use the tire jack that comes with this vehicle for replacing a flat tire.
Do not use it on other vehicles, and do no t use other tire jacks for replacing tires on
this vehicle.
●Always check that the tire jack is securely set to the jack point.
●Do not put any part of your body under the vehicle while it is supported by the jack.
●Do not start or run the engine while your vehicle is supported by the jack.
●Do not raise the vehicle while someone is inside.
●When raising the vehicle, do not put an object on or under the jack.
●Do not raise the vehicle to a height greater than that required to replace the tire.
●Use a jack stand if it is necessary to get under the vehicle.
●Vehicles with rear height control air suspensi on: Be sure to turn off the height control
and stop the engine.
Take particular care when lowering the ve hicle to ensure that no one working on or
near the vehicle will be injured.
■Using the jack handle
Tighten all the jack handle bo lts securely using a Phillips-head screwdriver, to prevent
the extension parts from co ming apart unexpectedly.

5487-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
Ensure that the shift lever is in P and depress the brake pedal.
Touch the Lexus emblem side of the
electronic key to the engine switch.
When the electronic key is detected, a
buzzer sounds and the engine switch
will turn to IGNITION ON mode.
When the smart access system with
push-button start is deactivated in cus-
tomization setting, the engine switch will
turn to ACCESSORY mode.
Firmly depress the brake pedal and check that is shown on the multi-
information display.
Press the engine switch shortly and firmly.
In the event that the engine still cannot be started, contact your Lexus dealer.
■Stopping the engine
Shift the shift lever to P and press the engine switch as you normally do when stopping
the engine.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the electronic
key battery be replaced immediately when the battery is depleted. ( P. 492)
■Changing engine switch modes
Within 10 seconds of the buzzer sounding, release the brake pedal and press the engine
switch.
The engine does not start and modes will be changed each time the switch is pressed.
(  P. 201)
■When the electronic key does not work properly
●Make sure that the smart access system wi th push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features:  P. 584)
●Check if battery-saving mode is set. If it is set, cancel the function. (P. 127)
Starting the engine
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5517-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
7
When trouble arises
Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximatel y 5 minutes to recharge the battery of
your vehicle.
Open and close any of the doors of your vehicle with the engine switch off.
Maintain the engine speed of the second vehicle and start the engine of your
vehicle by turning the engine switch to IGNITION ON mode.
Once your vehicle’s engine has started, remove the jumper cables in the exact
reverse order in which they were connected.
Once the engine starts, have the vehicle checked at your Lexus dealer as soon
as possible.
■Starting the engine when the battery is discharged
The engine cannot be started by push-starting.
■To prevent battery discharge
●Turn off the headlights and the audio system while the engine is off.
●Turn off any unnecessary electrical components when the vehicle is running at a low
speed for an extended period , such as in heavy traffic.
■Charging the battery
The electricity stored in the battery will disc harge gradually even when the vehicle is not
in use, due to natural discharge and the draini ng effects of certain electrical appliances. If
the vehicle is left for a long time, the battery may discharge, and the engine may be
unable to start. (The battery recharges automatically during driving.)
■When recharging or replacing the battery
●In some cases, it may not be possible to un lock the doors using the smart access system
with push-button start when the battery is discharged. Use the wireless remote control
or the mechanical key to lock or unlock the doors.
●The engine may not start on the first attempt after the battery has recharged but will
start normally after the second attempt. This is not a malfunction.
●The engine switch mode is memorized by the vehicle. When the battery is recon-
nected, the system will return to the mode it was in before the battery was discharged.
Before disconnecting the battery, turn the engine switch off. If you are unsure what
mode the engine switch was in before the battery discharged, be especially careful
when reconnecting the battery.
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5547-2. Steps to take in an emergency
GX460_OM_OM60T19U_(U)
The coolant level is satisfactory if it is between the “F” and “L” lines on the res-
ervoir.Reservoir
“F”
“L”
Radiator cap
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Start the engine and turn the air conditio ning system on to check that the radi-
ator cooling fans operate and to check for coolant leaks from the radiator or
hoses.
The fans operate when the air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air flow.
If it is difficult to check these, turn the air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately an d contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
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