2015 LEXUS RX450h Owners Manual

7845-2. Steps to take in an emergency
If the vehicle 12-volt battery is discharged The following procedures may be used to start the hybrid system if the vehi-
cle’s 12-volt battery is discharged.
You can also call your Lexus dealer or a qualified repair shop.
If you have a set of jumper (or booster) cables and a second vehicle
with a 12-volt battery, you can jump start your vehicle by following the
steps below.
Open the hood and remove the engine compartment covers.
(  P. 655)
Remove the fuse box cover and open the exclusive jump start-
ing terminal cover.
Connect the jumper cables according to the following procedure:
Connect a positive jumper cable clam p to the exclusive jump start-
ing terminal on your vehicle
Connect a positive jumper cable cl amp to the positive (+) battery
terminal on the second vehicle
Connect a negative cable clamp to the negative (-) battery terminal
on the second vehicle
Connect the clamp at the other end of the negative cable to a solid,
stationary, unpainted metallic point away from the exclusive jump
starting terminal and any moving part s, as shown in the illustration.STEP 1
STEP 2
STEP 3

5
When trouble arises
7855-2. Steps to take in an emergency
■
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 sy stem while the hybrid system is off.●
Turn off any unnecessary electrical compon ents when the vehicle is running at a
low speed for an extended period, such as in heavy traffic.■
When the 12-volt battery is removed or discharged ●
The power back door must be initialized.
(  P. 8 3 7 )●
The hybrid system may not start. (
 P. 6 6 8 )
●
Make sure that the key is not inside th e vehicle when recharging or replacing
the 12-volt battery. The key may be locked in the vehicle if the alarm is activated.
(  P. 1 2 8 ) Start the engine of the second vehicle. Increase the engine
speed slightly and maintain that level for approximately 5 min-
utes to recharge the 12-volt battery of your vehicle.
Open and close any of the doors of your vehicle with the
“POWER” switch off.
Maintain the engine sp eed of the second ve hicle and start the
hybrid system of your vehicle by turning the “POWER” switch
to ON mode.
Make sure the “READY” indicat or comes on. If the indicator
does not come on, contact your Lexus dealer.
Once the hybrid system has st arted, remove the jumper cables
in the exact reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at your
Lexus dealer as soon as possible. STEP 4
STEP 5
STEP 6
STEP 7
STEP 8

7865-2. Steps to take in an emergency
■
Charging the 12-volt battery
The electricity stored in the 12-volt batter y will discharge gradually even when the
vehicle is not in use, due to natural discharge and the draining effects of certain
electrical appliances. If the vehicle is left for a long time, the 12-volt battery may dis-
charge, and the hybrid system may be un able to start. (The 12-volt battery
recharges automatically while the hybrid system is operating.)
CAUTION■
Avoiding 12-volt battery fires or explosions
Observe the following precautions to prevent accidentally igniting the flammable
gas that may be emitted from the 12-volt battery: ●
Make sure each jumper cable is connecte d to the correct terminal and that it is
not unintentionally in contact with an y other than the intended terminal.●
Do not allow the other end of the jumper cable 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 jumper cables to come into contact with
each other.●
Do not smoke, use matches, cigarette lighters or allow open flame near the 12-
volt battery.■
12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic electrolyte, while
related parts contain lead and lead compounds. Observe the following precautions
when handling 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 co me into 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, immedi-
ately 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.

5
When trouble arises
7875-2. Steps to take in an emergency
CAUTION●
Always wash your hands after handling the 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 your Lexus dealer as soon as possible.
If the 12-volt battery is deteriorating, co ntinued 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
 P. 6 6 9
NOTICE■
When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in
the cooling fans or belt.■
Avoiding accidental short-circuits
When connecting jumper cables, observe the following precautions: ●
Make sure each jumper cable is connected to the correct terminal.●
Do not allow the ends of the jumper cable used for the “+” terminals 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 “-” terminals of the jumper cables to come into contact
with each other.■
Exclusive jump starting terminal precaution
The exclusive jump starting terminal is to be used when charging the 12-volt battery
from another vehicle in an emergency. It cannot be used to jump start another vehi-
cle.

7885-2. Steps to take in an emergency
If your vehicle overheats
Correction procedures
■ If “ENGINE OVERHEAT” is shown on the multi-information display
Stop the vehicle in a safe place and turn off the air conditioning
system, and then stop the hybrid system.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the hybrid system has cooled
down sufficiently, inspect the hoses
and radiator core (radiator) for any
leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact your Lexus
dealer.The following may indicate that your vehicle is overheating.
● “ENGINE OVERHEAT” is shown on the multi-information display:
The engine may be overheating.
● “HYBRID SYSTEM OVERHEAT” is sh own on the multi-information
display:
A hybrid system component such as the power control unit or an
electric motor (traction motor) may be overheating.
● Steam comes out from under the hood. STEP 1
STEP 2
STEP 3

5
When trouble arises
7895-2. Steps to take in an emergency
The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” line
Radiator cap
Add coolant if necessary. (
 P. 6 5 5 )
Water can be used in an emer-
gency if coolant is unavailable.
Start the hybrid system and turn the air conditioning system on to
check that the radiator 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 immedi-
ately after a cold start. Confirm that the fans are operating by checking
the fan sound and air flow. If it is diff icult to check these, turn the air con-
ditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)STEP 4
STEP 5
STEP 6

7905-2. Steps to take in an emergency
If the fans are not operating:
Stop the hybrid system immediately and contact your Lexus
dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
■ If “HYBRID SYSTEM OVERHEAT” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place. Ensure that the opening for the oil
cooler is not blocked by dirt or any
other foreign substance. If the
opening is not blocked or if the
message does not disappear after
some time the opening has been
cleaned, proceed to STEP 2.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled
down, inspect the hoses and radia-
tor core (radiator) for any leaks.
Radiator
Cooling fans If a large amount of coolant leaks,
immediately contact your Lexus
dealer.
The coolant level is satisfactory if it
is between the “FULL” and “LOW”
lines on the reservoir.
Reservoir
“FULL” line
“LOW” lineSTEP 7
STEP 1
STEP 2
STEP 3
STEP 4

5
When trouble arises
7915-2. Steps to take in an emergency
Add coolant if necessary. Water can be used in an emer-
gency if coolant is unavailable.
Start the hybrid system and check for the multi-information dis-
play.
If the message does not disappear:
Stop the hybrid system and contact your Lexus dealer.
If the message is not displayed:
Have the vehicle inspected at the nearest Lexus dealer.STEP 5
CAUTION■
To prevent an accident or injury when in specting under the hood of your vehicle●
If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartm ent may be very hot, causing serious
injuries such as burns.●
After the hybrid system has been turned off, check that the indicator on the
“POWER” switch and the “READY” indicator are off.
When the hybrid system is operating, the gasoline engine may automatically
start, or the cooling fans may suddenly operate even if the gasoline engine stops.
Do not touch or approach rotating parts such as the fans, which may lead to fin-
gers or clothing (especially a tie, a scarf or a muffler) getting caught, resulting in
serious injury.●
Do not loosen the radiator cap while the hybrid system and radiator are hot.
Serious injuries, such as burns, may re sult from hot coolant and steam released
under pressure. STEP 6