2010 Lexus HS250h Owner's Manual

5
When trouble arises
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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)To change “POWER” switch modes: Within 10 seconds of the
buzzer sounding, release the brake pedal and press the
“POWER” switch. Modes can be changed each time the switch is
pressed. (
→P. 1 4 6 )
To start the hybrid system: Press the “POWER” switch within 10
seconds of the buzzer sounding, keeping the brake pedal
depressed.
In the event that the hybrid system still cannot be operated, contact your
Lexus dealer.
■Stopping the hybrid system
In the same method as the normal hybrid system stopping procedure, completely
stop the vehicle and then press the “POWER” switch.
■Replacing the key battery
As the above procedure is a temporary measure, it is recommended that the elec-
tronic key battery be replaced immediately when the battery is depleted.
( → P. 4 5 3 )
■When the electronic key does not work properly
Make sure that the smart access system with push-button start has not been deacti-
vated in the customization setting. If it is off, turn the function on.
(Customizable features →P. 5 74 )

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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
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 fuse box
cover.
Push the tab in and lift the lid off.
Open the exclusive jump start-
ing terminal cover.
Slightly pull the tab to open the
cover.

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When trouble arises
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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
Connect the jumper cables according to the following procedure:Connect a positive jumper cable clamp to the exclusive jump start-
ing terminal on your vehicle
Connect the clamp on the other end of the positive cable to the pos-
itive (+) 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 parts, as shown in the illustration. 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.
Maintain the engine speed of th e second vehicle and start the
hybrid system of your vehicle by turning the “POWER” switch
to ON mode.
Make sure the “READY” indicator comes on. If the indicator
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.

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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
■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 components when the vehicle is running at a
low speed for an extended period, such as in heavy traffic.
■When the 12-volt battery is discharged
●The hybrid system may not start. (→P. 434)
●If the 12-volt battery is depleted with the shift position in P, it will not be possible
to shift out of P. In this case, the vehicle cannot be towed without lifting both
front wheels because the front wheels are locked by the parking lock.
(→ P. 4 8 3 )
●When the 12-volt battery is reconnected, start the hybrid system, depress the
brake pedal, and confirm that it is possible to shift into each shift position.
Close the exclusive jump starting terminal cover and reinstall
the fuse box cover.
Once the hybrid system starts, ha ve the vehicle inspected at your
Lexus dealer as soon as possible.

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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
CAUTION
■Avoiding battery fires or explosions
The flammable gas that may be generated by the assisting vehicle battery may
catch fire and explode. Make sure to observe the following to prevent fire or sparks.
●Make sure each jumper cable is connected to the correct terminal and that it is
not unintentionally in contact with any part 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 allow open flame or use matches, cigarette lighters or smoke near the
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 come 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.
●Always wash your hands after handling the battery support, terminals, and other
battery-related parts.
●Do not allow children near the 12-volt battery.

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5-2. Steps to take in an emergency
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NOTICE
■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.
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in
the cooling fans or belt.

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When trouble arises
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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)
If your vehicle overheats
Correction procedures■ If the engine coolant temperature warning light comes on or flashes
Stop the vehicle in a safe place and turn off the air conditioning
system.
Check to see if steam is coming out from the engine area.
If you see steam:
Stop the hybrid system. Carefully lift the hood after the steam
subsides and then restart the hybrid system.
If you do not see steam:
Leave the hybrid system operating and carefully lift the hood.
Remove the engine compartment cover. ( →P. 423)
Check to see if the cooling fans are operating.
If the fans are operating:
Wait until the high engine coolant temperature warning light goes
off and then stop the hybrid system.
If the fans are not operating:
Stop the hybrid system immediately and call your Lexus dealer.
The following may indicate that your vehicle is overheating:
● The high engine coolant temperature warning light comes on or
flashes:
The engine may be overheating.
● “HYBRID SYSTEM OVERHEAT” is shown on the multi-information
display:
The power control unit may be overheating.
Follow the correction procedure as described below.

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5-2. Steps to take in an emergency
HS250h_U_75033U(Canada)After the hybrid system has cooled
down sufficiently, check the engine
coolant level and inspect the cool-
ing system for leaks.
Add engine coolant if necessary.
Water can be used in an emer-
gency if engine coolant is unavail-
able. (
→P. 5 5 4 )
Have the vehicle inspected at the nearest Lexus dealer as soon as possi-
ble.
■If “HYBRID SYSTEM OVERHEAT” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place and turn off the air conditioning
system.
Leave the hybrid system operating and carefully lift the hood.
Remove the engine compartment covers. ( →P. 423)
Check if the cooling fans are operating.
If the fans are operating:
Wait until the “HYBRID SYSTEM OVERHEAT” message disap-
pears and then stop the hybrid system.
If the message does not disappear, call your Lexus dealer.
If the fans are not operating:
Stop the hybrid system immediat ely and call your Lexus dealer.