ignition LEXUS RX350 2016 Repair Manual

5717-3. Do-it-yourself maintenance
7
Maintenance and care
RX350_U_OM48E90U * : Vehicles with sing le-beam headlightsTire inflation pres-
sure (  P. 5 9 3 ) • Tire pressure gauge • Compressed air source
Wa s h e r f l u i d
(  P. 5 8 3 ) • Water or washer fluid containi ng antifreeze (for winter use)
• Funnel (used only for adding water or washer fluid)
WA R N I N G
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energized. To avoid death or serious injury, observe
the following precautions. ■
When working on the engine compartment ●
Keep hands, clothing and tools away from the moving fan and engine drive belt.●
Be careful not to touch the engine, radiator, exhaust manifold, etc. right after driving
as they may be hot. Oil and other fluids may also be hot. ●
Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment. ●
Do not smoke, cause sparks or expose an open flame to fuel or the battery. Fuel and
battery fumes are flammable. ●
Be extremely cautions when working on the battery. It contains poisonous and corro-
sive sulfuric acid. ■
When working near the electric cooling fans or radiator grille
Be sure the engine switch is off.
With the engine switch in IGNITION ON mode, the electric cooling fans may auto-
matically start to run if the air conditioning is on and/or the coolant temperature is high.
(  P. 5 7 9 ) ■
Safety glasses
Wear safety glasses to prevent flying or fallin g material, fluid spray, etc. from getting in
your eyes.
NOTICE ■
If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to dirt
in the air. Items Pa r t s a n d t o o l s

586 7-3. Do-it-yourself maintenance
RX350_U_OM48E90U ■
How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the engine switch off. Initialization cannot be performe d while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation pressure
level. (  P. 6 8 0 )Make sure to adjust the tire pressure to the specified cold tire inflation pressure
level. The tire pressure warning system w ill operate based on this pressure level.
Turn the engine switch to IGNITION ON mode.
Select on the multi-information display. (  P. 9 6 )
Press or of the meter con-
trol switch, select the “TPMS”
screen and then press and hold
the
until the tire pressure
warning light blinks slowly 3
times. “- -” will be displayed for inflation
pressure of each tire on the multi-
information display while the tire
pressure warning system determines
the position of each tire.
When position of each tire is determined, the inflation pressure of each tire will be
displayed on the multi-information display.
Drive the vehicle at approximately 25 mph (40 km/h) or more for approx-
imately 10 to 30 minutes until the inflat ion pressure of each tire is displayed
on the multi-information display. If tire inflation pressure becomes low before the inflation pressure is displayed, the
tire pressure warning light will come on.
Depending on the vehicle and driving conditions, initializati on may take up to
approximately 1 hour to complete.
◆ Registering ID codes
The tire pressure warning valve and transmitter is equipped with a unique ID
code. When replacing a tire pressure warning valve and transmitter, it is nec-
essary to register the ID code. Have the ID code registered by your Lexus
dealer. 1
2
3
4
5
6

6298-2. Steps to take in an emergency
8
When trouble arises
RX350_U_OM48E90U Take out the towing eyelet. (  P. 6 4 7 )
Remove the eyelet cover.
Insert the towing eyelet into the hole
and tighten partially by hand.
Tighten down the towing eyelet
securely using a wheel nut wrench
or hard metal bar.
Securely attach cables or chains to the towing eyelet.
Take care not to damage the vehicle body.
Enter the vehicle being towed and start the engine.
If the engine does not start, turn th e engine switch to IGNITION ON mode.
Shift the shift lever to N and release the parking brake.
When the shift lever cannot be shifted:  P. 6 6 0Emergency towing procedure (vehicles with a towing eyelet) 1
2
3
4
5
6
7

6378-2. Steps to take in an emergency
8
When trouble arises
RX350_U_OM48E90U * : Driver's and front passenger' 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 IGNITION ON mode, the
buzzer sounds for 6 seconds. If the vehicl e reaches a speed of 12 mph (20 km/h), the
buzzer sounds once. If the seat belt is still unfastened afte r 24 seconds, the buzzer will
sound intermittently for 10 seconds. Then, if the seat belt is still unfastened, the buzzer
will sound in a different tone for 20 more seconds.
The front passenger’s seat belt warning buzzer sounds to alert the front passenger
that his or her seat belt is not fastened. The buzzer sounds once if the vehicle reaches
a speed of 12 mph (20 km/h). If the seat belt is still unfastened after 24 seconds, the
buzzer will sound intermittently for 10 seconds. Then, if the seat belt is still unfastened,
the buzzer will sound in a different tone for 20 more seconds. ■
SRS warning light
This warning light system monitors the airbag sensor assembly, front impact sensors, side
impact sensors (front door), side impact se nsors (rear), driver’s seat position sensor,
driver’s seat belt buckle swit ch, front passenger occupant classification system (ECU and
sensors), “AIR BAG ON” indicator light, “A IR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, driver’s seat belt pretensioner, front passenger’s seat belt
pretensioner and force limiter, airbags, in terconnecting wiring and power sources.
(  P. 3 6 ) ■
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 th e seat, the sensor may not detect a passenger, and the warn-
ing light may not operate properly. ■
Electric power steering system warning light (warning buzzer)
When the battery charge becomes insufficie nt of the voltage te mporarily drops, the
electric power steering system warning light may come on and the warning buzzer may
sound. ■
If the malfunction indicator lamp comes on while driving
First check the following: ●
Is the fuel tank empty?
If it is, fill the fuel 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.

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

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

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

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

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

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.