2018 LEXUS RX450h light

688 8-2. Steps to take in an emergency
RX450h_RX450hL _U_OM48F85UWARNING ■
When using the compact spare tire ●
Remember that the compact spare tire provid ed is specifically designed for use with
your vehicle. Do not use your comp act spare tire on another vehicle.●
Do not use more than one comp act spare tire simultaneously.●
Replace the compact spare tire with a standard tire as soon as possible.●
Avoid sudden acceleration, abrupt steering, sudden braking and shifting operations
that cause sudden engine braking. ■
When the compact spare tire is attached
The vehicle speed may not be correctly detected, and the following systems may not
operate correctly:
Also, not only can the following system not be utilized fully, but it may even negatively
affect the drive-train components:
•E-Four ■
Speed limit when using the compact spare tire
Do not drive at speeds in excess of 50 mph (80 km/h) when a compact spare tire is
installed on the vehicle.
The compact spare tire is not designed for driving at high speeds. Failure to observe
this precaution may lead to an accid ent causing death or serious injury.■
After using the tools and jack
Before driving, make sure all the tools and jack are securely in place in their storage
location to reduce the possibilit y of personal injury during a collision or sudden brak-
ing.• ABS & Brake assist
•VSC
•TRAC
•EPS
• Trailer Sway Control
•VDIM
• Adaptive Variable Suspension System
(if equipped)
• Dynamic radar cruise control with full-
speed range
• PCS (Pre-Collision System)
• LKA (Lane-Keeping Assist) • Automatic High Beam
• AFS (Adaptive Front-lighting System)
(if equipped)
• Tire pressure warning system
• Intuitive parking assist (if equipped)
• Intelligent Clearance Sonar (ICS) (if
equipped)
• Lexus parking assist monitor (if
equipped)
• Panoramic view monitor (if equipped)
• BSM (Blind Spot Monitor) (if
equipped)
• Navigation system (if equipped)

690 8-2. Steps to take in an emergency
RX450h_RX450hL _U_OM48F85UOne of the following may be the cause of the problem: ●
The electronic key may not be functioning properly.
( → P. 692)●
There may not be sufficient fuel in the vehicle’s tank.
Refuel the vehicle. ●
There may be a malfunction in the immobilizer system. ( → P. 83)●
There may be a malfunction in the steering lock system. ●
The hybrid system may be malfunctioni ng due to an electrical problem such
as electronic key battery depletion or a blown fuse. However, depending on
the type of malfunction, an interim meas ure is available to start the hybrid sys-
tem. ( → P. 691)
One of the following may be the cause of the problem: ●
The 12-volt battery may be discharged. ( → P. 695)●
The 12-volt battery terminal connections may be loose or corroded.
( → P. 691)If the hybrid system will not start Reasons for the hybrid system not star ting vary depending on the situation.
Check the following and perform the appropriate procedure:
The hybrid system will no t start even though the correct starting proce-
dure is being followed. ( → P. 239)
The interior lights and headlights are d im, or the horn does not sound or
sounds at a low volume.

6918-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL _U_OM48F85UOne of the following may be the cause of the problem: ●
The 12-volt battery may be discharged. ( → P. 695)●
One or both of the 12-volt battery terminals may be disconnected. ( → P. 605)Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
When the hybrid system does not start, the following steps can be used as an
interim measure to start the hybrid system if the power switch is functioning nor-
mally.
Do not use this starting procedur e except in cases of emergency.
Turn the power switch to ON mode an d check that the parking brake is set.
( → P. 240, 253)
Shift the shift lever to P.
Turn the power switch to ACCESSORY mode.
Press and hold the power switch for ab out 15 seconds while depressing the
brake pedal firmly.
Even if the hybrid system can be starte d using the above steps, the system may
be malfunctioning. Have the vehicle inspected by your Lexus dealer.The interior lights and headlights do not turn on, or the horn does not
sound.
Emergency start function 1
2
3
4

6978-2. Steps to take in an emergency
8
When trouble arises
RX450h_RX450hL _U_OM48F85UStart the engine of the second vehicle. Increase the engine speed slightly and
maintain at that level for approximatel y 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of yo ur vehicle with the power switch off.
Maintain the engine speed of the seco nd vehicle and start the hybrid system
of your vehicle by turning th e power switch to ON mode.
Make sure the “READY” indicator comes on. If the indicator light does not
come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Close the exclusive jump starting termin al cover, and reinstall the fuse box
cover to its original position.
Once the hybrid system starts, have th e vehicle inspected at your Lexus dealer
as soon as possible. ■
Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting. ■
To prevent 12-volt battery discharge ●
Turn off the headlights and the audio system while the hybrid system is off. ●
Turn off any unnecessary electrical componen ts when the vehicle is running at a low
speed for an extended period , such as in heavy traffic.■
When removing the battery terminals
When the battery terminals are removed, the information stored in the ECU is cleared.
Before removing the battery termin als, contact your Lexus dealer.6
7
8
9
10
11

700 8-2. Steps to take in an emergency
RX450h_RX450hL _U_OM48F85UWARNING ■
Avoiding 12-volt battery fires or explosions
Observe the following precautions to preven t accidentally igniting the flammable gas
that may be emitted from the 12-volt battery: ●
Make sure each jumper cable is connected to the correct terminal and that it is not
unintentionally in contact with any other than the intended terminal.●
Do not allow the other end of the jumper cab le connected to the “+” terminal to come
into contact with any other parts or metal surfaces in the area, such as brackets or
unpainted metal. ●
Do not allow the + and - clamps of the jump er cables to come in to contact with each
other. ●
Do not smoke, use matches, cigarette light ers or allow open flame near the 12-volt
battery. ■
12-volt battery precautions
The 12-volt battery contains poisonous and co rrosive acidic electr olyte, while related
parts contain lead and lead compounds. Ob serve the following precautions when han-
dling the 12-volt battery: ●
When working with the 12-volt battery, always wear safety glasses and take care not
to allow any battery fluids (acid) to come in to contact with skin, clothing or the vehicle
body. ●
Do not lean over the 12-volt battery. ●
In the event that battery fluid comes into contact with the skin or eyes, immediately
wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medical attention can be
received. ●
Always wash your hands after handling the 12-volt battery support, terminals, and
other battery-related parts. ●
Do not allow children near the 12-volt battery. ■
After recharging the 12-volt battery
Have the 12-volt battery inspected at yo ur Lexus dealer as soon as possible.
If the 12-volt battery is deteriorating, continued use may cause the 12-volt battery to
emit a malodorous gas, which may be de trimental to the health of passengers.■
When replacing the 12-volt battery ●
When the vent plug and indicator are close to the hold down clamp, the battery fluid
(sulfuric acid) may leak. ●
For information regarding 12-volt battery replacement, contact your Lexus dealer.●
Make sure to replace the 12-volt battery with one designed for this vehicle. Other-
wise, hydrogen gas may enter the vehicle, possibly causing a fire or explosion. ●
After replacing, securely attach the exhaust hose and exhaust hole plug to the
exhaust hole of the replaced 12-volt battery. If not properly installed, gases (hydro-
gen) may leak into the vehicle interior, an d there is the possible danger of the gas
igniting and exploding.

7159-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85U* : The coolant capacity is a reference quantity.
If replacement is necessary, contact your Lexus dealer.Cooling system Capacity
* Gasoline
engine 
RX450h
10.7 qt. (10.1 L, 8.9 Imp. qt.) 
RX450hL
13.2 qt. (12.5 L, 11 Imp. qt.)
Power control
unit 2.0 qt. (1.9 L, 1.7 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 12-volt 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 hybrid
system and all lights are turned off.)
Charging rates 5 A max.

7199-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85ULight bulbs Light bulbs Bulb No. W Type
Exterior Front side marker lights
* 1
⎯ 5 B
Front turn signal lights
* 1
7444NA 28/8 A
Rear turn signal lights
* 1
⎯ 21 A
Back-up lights 921 16 B
Interior Door courtesy lights
* 2
⎯ 5 B
Vanity lights ⎯ 8 B
Luggage compartment light ⎯ 5 B
A: Wedge base bulbs (amber)
B: Wedge base bulbs (clear)
* 1
: Vehicles with single-beam headlights
* 2
: Vehicles without door trim ornament lights

7219-1. Specifications
9
Vehicle specifications
RX450h_RX450hL _U_OM48F85U■
Recommendation of the use of low emissions gasoline
Gasolines containing oxygenates such as et hers and ethanol, as well as reformulated
gasolines, are available in some cities. Thes e fuels are typically acceptable for use, pro-
viding they meet other fuel requirements.
Lexus recommends these fuels, since the form ulations allow for reduced vehicle emis-
sions. ■
Non-recommendation of the use of blended gasoline
●
If you use gasohol in your vehicle, be sure that it has an octane ra ting no lower than 91.●
Lexus does not recommend the use of gasoline containing methanol. ■
Non-recommendation of the use of gasoline containing MMT
Some gasoline contains an octane enhancing additive called MMT
(Methylcyclopentadienyl Manganese Tricarbonyl).
Lexus does not recommend the use of gasoline that contains MMT. If fuel containing
MMT is used, your emission control system may be ad versely affected.
The malfunction indicator lamp on the instru ment cluster may come on. If this happens,
contact your Lexus dealer for service. ■
If your engine knocks ●
Consult your Lexus dealer. ●
You may occasionally notice light knocking for a short time while accelerating or driv-
ing uphill. This is normal and there is no need for concern.●
Use only gasoline containing up to 15% etha-
nol.
DO NOT use any flex-fuel or gasoline that
could contain more than 15% ethanol, includ-
ing from any pump labeled E30, E50, E85
(which are only some examples of fuel con-
taining more than 15% ethanol). DO NOT use gasoline
containing more than
15% ethanol.
(30% ethanol)
(50% ethanol)
(85% ethanol)