Page 638 of 748

638 8-2. Steps to take in an emergency
RX350_U_OM48E90U ■
When the tire pressure warning light comes on
Inspect the tires to check if a tire is punctured.
If a tire is punctured: P. 6 4 6
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 blinks.
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. 5 8 6 )
If the warning light does not turn off several minutes after the initia lization has been per-
formed, have the vehicle inspected by your Lexus dealer immediately.
If the tire pressure warning light blinks for 1 minute then stays 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 come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air
leaks and 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 compact spare tire is not equipped with a tire pressure warning valve and transmit-
ter. If a tire goes flat, the tire pressure warning light will not turn off even though the flat
tire has been replaced with the spare tire. Replace the spare tire with the repaired tire
and adjust the tire inflation pressure. The tire pressure warning light will go off after a few
minutes. ■
Conditions that the tire pressure warning system may not function properly
P. 5 8 9 ■
Warning buzzer
In some cases, the buzzer may not be heard due to being in a noisy location or audio
sound. ■
Customization
Some functions can be customized. ( P. 6 9 9 )1
2
Page 659 of 748

6598-2. Steps to take in an emergency
8
When trouble arises
RX350_U_OM48E90U 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. 6 6 5 )●
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.
When the engine does not start, the following steps can be used as an interim
measure to start the engine if the engine switch is functioning normally.
T urn the engine switch to IGNITION ON mode and check that the parking
brake is set. ( P. 221, 235)
Shift the shift lever to P.
Turn the engine switch to ACCESSORY mode.
Press and hold the engine 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 mal-
functioning. Have the vehicle inspected by your Lexus dealer.The starter motor does not turn ove r, the interior lights and headlights
do not turn on, or the horn does not sound.
Emergency start function 1
2
3
4
Page 660 of 748
660 8-2. Steps to take in an emergency
RX350_U_OM48E90U T urn the engine switch to IGNITION ON mode and check that the parking
brake is set. ( P. 221, 235)
Turn the engine switch to ACCESSORY mode.
Depress the brake pedal.
Pry the cover up with a flathead
screwdriver or equivalent tool. To prevent damage to the cover, cover
the tip of the screwdriver with a rag.
Press the shift lock override button. The shift lever can be shifted while the
button is pressedIf the shift lever cannot be shifted from P If the shift lever cannot be shifted with your foot on the brake pedal, there may
be a problem with the shift lock system (a system to prevent accidental opera-
tion of the shift lever). Have the vehicl e inspected by your Lexus dealer imme-
diately.
The following steps may be used as an emergency measure to ensure that the
shift lever can be shifted: 1
2
3
4
5
Page 663 of 748
6638-2. Steps to take in an emergency
8
When trouble arises
RX350_U_OM48E90U 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
customization 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.
In the event that the engine still cannot be started, contact your Lexus dealer.Starting the engine 1
2
3
4
Page 666 of 748

666 8-2. Steps to take in an emergency
RX350_U_OM48E90U Connect the clamp at the other end of the negative cable to a solid, station-
ary, unpainted metallic point away from the battery and any moving parts,
as shown in the illustration.
Start the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximately 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 the vehicle’s engine has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the engine starts, have the vehicle inspected 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 discharge gradually even when the vehicle is not
in use, due to natural discharg e and the draining 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 the battery is removed or discharged ●
In some cases, it may not be possible to unlock 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. ●
The power back door must be initialized. ( P. 1 3 8 )4
4
5
6
7
Page 678 of 748

678 9-1. Specifications
RX350_U_OM48E90U * : The coolant capacity is a reference quantity.
If replacement is necessary, contact your Lexus dealer.Cooling system Capacity
*
Vehicles without towing package
9.5 qt. (9.0 L, 7.9 Imp. qt.)
Vehicles with towing package
10.5 qt. (9.9 L, 8.7 Imp. qt.)
Coolant type Use either of the following:
• “Toyota Super Long Life Coolant”
• Similar high-quality ethylene glycol-based
non-silicate, non-amine, non-nitrite, and non-
borate coolant with long-life hybrid organic
acid technology
Do not use plain water alone.
Ignition system (spark plug) Make DENSO FK20HBR8
Gap 0.03 in. (0.8 mm)
NOTICE ■
Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust the spark plug gap.
Electrical system Battery
Open voltage at 68 F (20 C): 12.6 V or higher: Fully charged
12.2 — 12.4 V: Half charged
12.0 V or lower: Discharged
(Voltage is checked 20 minutes after the engine
and all lights ar e turned off.)
Charging rates 5 A max.
Page 711 of 748

7119-2. Customization
9
Vehicle specifications
RX350_U_OM48E90U ■
Seat belt reminder ( P. 636)■
Vehicle customization ●
When the smart access system with push-but ton start is off, the entry unlock function
cannot be customized. ●
When the doors remain closed after unlocking the doors and the timer activated auto-
matic door lock function activates, signals will be generated in accordance with the
operation buzzer volume and operational si gnal (Emergency flashers) function set-
tings. ●
Some settings can be changed using a switch or the audio system screen. If a setting is
changed using a switch, the changed setting will not be reflected on the audio system
screen until the engine switch is turn ed off and then to IGNITION ON mode.Function Default setting Customized setting
Vehicle speed linked seat belt
reminder buzzer On Off — O
WA R N I N G ■
Cautions during customization
As the engine needs to be running during customization, ensure that the vehicle is
parked in a place with adequate ventilation. In a closed area such as a garage, exhaust
gases including harmful carbon monoxide (CO) may collect and enter the vehicle. This
may lead to death or a serious health hazard.
NOTICE ■
During customization
To prevent battery discharge, ensure that the engine is running while customizing fea-
tures. 1 2
Page 728 of 748

728
RX350_U_OM48E90U What to do if... (Troubleshooting)
What to do if... (Troubleshooting) ●
If you lose your mechanical keys, ne w genuine mechanical keys can be made
by your Lexus dealer. ( P. 1 2 1 )●
If you lose your electronic keys, the risk of vehicle theft increases significantly.
Contact your Lexus dealer immediately. ( P. 1 2 3 )●
Is the electronic key battery weak or depleted? ( P. 6 0 3 )●
Is the engine switch in IGNITION ON mode?
When locking the doors, turn the engine switch off. ( P. 221)●
Is the electronic key left inside the vehicle?
When locking the doors, make sure that you have the electronic key on your
person. ●
The function may not operate properly du e to the condition of the radio wave.
( P. 1 4 8 )
●
Is the child-protector lock set?
The rear door cannot be opened from inside the vehicle when the lock is set.
Open the rear door from outside and then unlock the child-protector lock.
( P. 1 2 7 )If you have a problem, check the following before contacting your Lexus
dealer.
The doors cannot be locked, unlocked, opened or closed You lose your keys
The doors cannot be locked or unlocked
The rear door cannot be opened