check engine light LEXUS RX350 2016 Owner's Manual

622 7-3. Do-it-yourself maintenance
RX350_U_OM48E90U ■
LED lights
The headlight low beams, headlight high beams, front turn signal lights (vehicles with tri-
ple-beam headlights), parking lights and dayt ime running lights, front fog lights, corner-
ing lights (if equipped), front side marker lights (vehicles with tr iple-beam headlights),
side turn signal lights, stop/t ail lights, rear turn signal lig ht (vehicles with triple-beam
headlights), rear side marker lights, high moun ted stoplight, license plate lights, and outer
foot lights consist of a number of LEDs. If an y of the LEDs has burned out, take your vehi-
cle to your Lexus dealer to have the light replaced. ■
Condensation build-up on the inside of a lens
Temporary condensation build-up on the inside of the headlight lens does not indicate a
malfunction. Contact your Lexus dealer for mo re information in the following situations:●
Large drops of water have built up on the inside of a lens.●
Water has built up inside a headlight. ■
When replacing light bulbs
 P. 6 0 6
WA R N I N G ■
To p r e v e n t i n j u r y
Before performing any light bulb replacement procedure, be sure to turn the engine
switch off. Failure to do so may result in burns from hot components or a part of your
body may get caught on an operating comp onent, possibly causing serious injury.■
Replacing light bulbs ●
Turn off the lights. Do not attempt to replace the bulb immediately after turning off the
lights.
The bulbs become very hot and may cause burns. ●
Do not touch the glass portion of the light bulb with bare hands. When it is unavoid-
able to hold the glass portion, use and ho ld with a clean dry cloth to avoid getting
moisture and oils on the bulb.
Also, if the bulb is scratched or dropped, it may blow out or crack.●
Fully install light bulbs and any parts used to secure them. Failure to do so may result
in heat damage, fire, or water entering the headlight unit. This may damage the head-
lights or cause condensation to build up on the lens.●
Do not attempt to repair or disassemble the light bulbs, connectors, electric circuits
or component parts.
Doing so may result in death or se rious injury due to electric shock.■
To prevent damage or fire ●
Make sure bulbs are fully seated and locked. ●
Check the wattage of the bulb before installin g to prevent heat damage.

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

6438-2. Steps to take in an emergency
8
When trouble arises
RX350_U_OM48E90U Take the appropriate actions as in structed in the message displayed.
If any of the following messages are displa yed, also refer to this Owner’s Manual.■
If “Shift to P Before Exiting Vehicle” is shown
Message is displayed when the driver’s door is opened without turning the
engine switch off with the shift lever in any position other than P.
Shift the shift lever to P. ■
If “Power Turned Off to Save Battery” is displayed
This message is displayed when the power was cut off due to the automatic
power off function.
The next time the engine is started, increase the engine speed slightly and
maintain it at that spee d for approximately 5 minutes to recharge the battery.■
If “AWD System Overheated Switching to 2WD Mode” or “AWD System
Overheated 2WD Mode Engaged” is displayed (AWD models)
This message may be displayed when driving under extremely high load con-
ditions.
Drive the vehicle at low speeds or stop the vehicle in a safe place with the
engine running until the message is cleared.
If the message is not cleared, have the vehicle inspected by your Lexus dealer.■
If “A New Key has been Registered Contact Your Dealer for Details” is dis-
played
This message will be displayed each time the driver’s door is opened when the
doors are unlocked from the outside for approximately one week after a new
electronic key has been registered.
If this message is displayed but you have not had a new electronic key regis-
tered, ask your Lexus dealer to check if an unknown electronic key (other than
those in your possession) has been registered. ■
When “Headlight System Malfunctio n Visit Your Dealer” is displayed
The following systems may be malfunct ioning. Have the vehicle inspected by
your Lexus dealer immediately. ●
The LED headlight system ●
The automatic headlight leveling system ●
Automatic High Beam (if equipped) ●
AFS (Adaptive Front-lighting System) (if equipped)Other messages displayed on the multi-information display

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

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.

730 What to do if... (Troubleshooting)
RX350_U_OM48E90U ●
The seat belt reminder light is flashing
Are the driver and the front passenger wearing the seat belts? (  P. 636)●
The parking brake indicator is on
Is the parking brake released? (  P. 2 3 5 )
Depending on the situation, other type s of warning buzzer may also sound.
(  P. 6 3 4 , 6 4 1 ) ●
Did anyone inside the vehicle open a door during setting the alarm?
The sensor detects it and the alarm sounds. (  P. 76 )
Do one of the following to stop the alarms: • Unlock the doors.
• Turn the engine switch to ACCESSORY or IGNITION ON mode, or start the
engine.
●
Is the message displayed on the multi-information display?
Check the message on the multi-information display. (  P. 6 4 1 )
●
When a warning light turns on or a warning message is displayed, refer to
P. 6 3 4 , 6 4 1 . A warning buzzer sounds during driving
An alarm is activated and the horn sounds
A warning buzzer sounds when leaving the vehicle
A warning light turns on or a warning message is displayed

735Alphabetical index
RX350_U_OM48E90U Coolant
Capacity ................................................ 678
Checking............................................... 578
Preparing and checking
before winter ................................... 380
Cooling system ..................................... 578
Engine overheating.......................... 668
Cornering lights .................................... 242
Cruise control
Cruise control......................................326
Dynamic radar cruise control....... 314
Dynamic radar cruise control
with full-speed range ................... 302
Cup holders ..............................................514
Curtain shield airbags ........................... 37
Customizable features ....................... 699
Customized mode ............................... 369
Daytime running light system .......... 243
Defogger
Outside rear view mirrors ............ 500
Rear window .......................................500
Windshield ........................................... 500
Differential ............................................... 679
Dimension ............................................... 674
Dinghy towing..........................................219
Display
Dynamic radar cruise control....... 314
Dynamic radar cruise control
with full-speed range ................... 302
LDA (Lane Departure Alert
with steering control) ................... 297
LKA (Lane-Keeping Assist) ........ 288
Multi-information display ..................89
Warning messages............................ 641 Do-it-yourself maintenance............. 570
Doors
Automatic door locking and
unlocking system.............................. 127
Door lock................................................. 126
Outside rear view mirrors .............. 173
Power back door ............................... 130
Rear door child-p rotectors ............ 127
Side doors ............................................... 124
Side windows ........................................ 177
Drive information .....................................93
Drive-start control .......... 193, 227, 232
Driver’s seat belt reminder light .... 636
Driver’s seat position memory.......... 162
Driving
Break-in tips ...........................................194
Correct posture .................................... 28
Driving mode select switch .......... 369
Procedures ............................................. 192
Winter drive tips ............................... 380
Driving position memory .................... 162
Memory recall function ....................165
Dynamic radar cruise control ........... 314
Dynamic radar cruise control
with full-speed range....................... 302
Dynamic Torque Control AWD
system .....................................................375D

736 Alphabetical index
RX350_U_OM48E90U Eco drive mode ..................................... 369
Eco Driving Indicator........................... 104
EDR (Event data recorder) ...................10
Electric Power Steering (EPS) ....... 374
Warning light ...................................... 635
Electronic key ......................................... 120
Battery-saving function .....................147
If the electronic key does not
operate properly.............................. 661
Replacing the battery ...................... 603
Emergency flashers ............................. 624
Emergency, in case of
If a warning buzzer sounds...........634
If a warning light turns on...............634
If a warning message is
displayed.............................................. 641
If the battery is discharged ........... 665
If the electronic key does not
operate properly.............................. 661
If the engine will not start............... 658
If you have a flat tire ......................... 646
If you lose your keys .................. 121, 123
If you think something is
wrong ...................................................632
If your vehicle becomes stuck .......671
If your vehicle has to
be stopped in an emergency ...625
If your vehicle needs to be
towed....................................................626
If your vehicle overheats ............... 668 Engine
ACCESSORY mode ....................... 221
Compartment ..................................... 574
Engine switch ...................................... 220
Hood........................................................ 572
How to start the engine.................. 220
Identification number ....................... 676
If your vehicle has to be
stopped in an emergency.......... 625
Ignition switch (engine switch) ... 220
Overheating........................................ 668
Engine coolant
Capacity ................................................. 678
Checking ............................................... 578
Preparing and checking
before winter ................................... 380
Engine coolant temperature
gauge ........................................................ 85
Engine immobilizer system .................. 74
Engine oil
Capacity ................................................. 676
Checking ............................................... 575
Preparing and checking
before winter ................................... 380
Engine switch ......................................... 220
Enhanced VSC ......................................374
EPS
(Electronic Power Steering) .........374
Warning light .......................................635
Event data recorder (EDR)................... 10E