LEXUS GS300H 2019 Owners Manual

5317-2. Steps to take in an emergency
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When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
GS450h: Remove the engine cover.
Connect the jumper cables according to the following procedure:
GS450h
GS300h
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5327-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
Connect a positive jumper cable clamp to the exclusive jump starting ter-
minal on your vehicle.
Connect the clamp on the other end of the positive cable 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, station-
ary, 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 at that level for approximately 5 minutes to recharge the 12-volt bat-
tery of your vehicle.
Open and close any of the doors of your vehicle with the power switch off.
Maintain the engine speed of the second vehicle and start the hybrid system
of your vehicle by turning the power switch to ON mode.
Make sure the “READY” indicator come s on. If the indicator does not come
on, contact any authorized Lexus retailer or Lexus authorized repairer, or any
reliable repairer.
Once the hybrid system has started, remove the jumper cables in the exact
reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at any authorized
Lexus retailer or Lexus authorized repairer, or any reliable repairer as soon as
possible.
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5337-2. Steps to take in an emergency
7
When trouble arises
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■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.
■Charging the 12-volt battery
The electricity stored in the 12-volt battery will discharge gradually even when the vehicle is not in use, due to natural discharge and the draining effects of certain electrical appli-ances. If the vehicle is left for a long time, the 12-volt battery may discharge, and the
hybrid system may be unable to start. (The 12-volt battery recharges automatically while the hybrid system is operating.)
■When recharging or replacing the 12-volt battery
●In some cases, it may not be possible to unlock the doors using the smart entry & startsystem when the 12-volt battery is discharged. Use the wireless remote control or themechanical key to lock or unlock the doors.
●The hybrid system may not start on the first attempt after the 12-volt battery hasrecharged but will start normally after the second attempt. This is not a malfunction.
●The power switch mode is memorized by the vehicle. When the 12-volt battery is
reconnected, the system will return to the mode it was in before the 12-volt battery was discharged. Before disconnecting the 12-v olt battery, turn the power switch off. If you are unsure what mode the power switch was in before the 12-volt battery dis-
charged, be especially careful when reconnecting the 12-volt battery.
WARNING
■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 connected to the correct terminal and that it is notunintentionally in contact with any 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.

5347-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■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 han-
dling the 12-volt battery:
●When working with the 12-volt battery, always wear safety glasses and take care not to allow any 12-volt 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 12-volt 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 bereceived.
●Always wash your hands after handling the 12-volt battery support, terminals, andother 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 any authorized Lexus retailer or Lexus autho- rized repairer, or any reliable repairer 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 detrimental to the health of passengers.
■When replacing the 12-volt battery
 P. 414
NOTICE
■When handling jumper cables
When connecting the jumper cables, ensure that they do not become entangled in the cooling fans or belt.
■To prevent damaging the vehicle
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 vehicle.

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7-2. Steps to take in an emergency
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
If your vehicle overheats
●The needle of the engine coolant temperature gauge ( P. 104) enters the
red zone or a loss of hybrid system power is experienced. (For example, the
vehicle speed does not increase.)
●“Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” or
“Hybrid System Overheated Reduced Output Power” ( P. 466) is shown on
the multi-information display.
●Steam comes out from under the hood.
■If the needle of the engine coolant temperature gauge enters the red zone
or “Engine Coolant Temp High Stop in a Safe Place See Owner’s Manual” 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
cooling system for leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact any autho-
rized Lexus retailer or Lexus authorized repairer, or any reli-able repairer.
The following may indicate that your vehicle is overheating.
Correction procedures
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5367-2. Steps to take in an emergency
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The coolant level is satisfactory if it is between the “FULL” and “LOW” lines
on the reservoir.
Reservoir
“FULL”
“LOW”
Coolant inlet cap
Add coolant if necessary. ( P. 539)
Water can be used in an emergency if engine coolant is unavailable.
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GS450hGS300h
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GS450hGS300h

5377-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
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 immediately after a
cold start. Confirm that the fans are op erating by checking the fan sound and air flow. If it is difficult to check these, tu rn the air conditioning system on and off repeatedly. (The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact any authorized Lexus
retailer or Lexus authorized repairer, or any reliable repairer.
If the fans are operating:
Have the vehicle inspected at the nearest any authorized Lexus retailer or
Lexus authorized repairer, or any reliable repairer.
■If “Hybrid System Overheated Reduced Output Power” is shown on the
multi-information display
Stop the vehicle in a safe place.
Stop the hybrid system and carefully lift the hood.
After the hybrid system has cooled down, inspect the hoses and radiator
core (radiator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks, immediately contact any autho-
rized Lexus retailer or Lexus authorized repairer, or any reli-able repairer.
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5387-2. Steps to take in an emergency
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The coolant level is satisfactory if it is between the “FULL”/“F” and “LOW”/
“L” lines on the reservoir.
Reservoir
“FULL”/“F”
“LOW”/“L”
Add coolant if necessary.
Water can be used in an emergency if po wer control unit coolant is unavailable.
Start the hybrid system and check for the multi-information display.
If the message does not disappear: Stop the hybrid system and contact any authorized Lexus retailer or Lexus autho-
rized repairer, or any reliable repairer.
If the message is not displayed: Have the vehicle inspected at the nearest any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
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GS450hGS300h
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GS450hGS300h
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5397-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
■When adding coolant
Add coolant in accordance with the following procedure.
Remove caps A and B.
Add coolant through the inlet of cap A up to the “[GR-HV] B” line/“[AR/GR] B” line,
and then install cap A.
Add coolant through the inlet of cap B un til it is full, and then install cap B.
GS300h only: When inst alling cap B, apply coolant to the O-ring on the end of cap B.
Cap A
Cap B
GS450h: “[GR-HV] B” line (Target fill line) GS300h: “[AR/GR] B” line (Target fill line)
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GS300h GS450h
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5407-2. Steps to take in an emergency
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■When inspecting under the hood of your vehicle
Observe the following precautions. Failure to do so may result in serious injury such as burns.
●If steam is seen coming from under the h ood, do not open the hood until the steam has subsided. The engine compartment may be very hot.
●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, orthe cooling fan may suddenly operate even if the gasoline engine stops. Do not touch
or approach rotating parts such as the fan, which may lead to fingers or clothing (especially a tie, a scarf or a muffler) getting caught, resulting in serious injury.
●Do not loosen the coolant inlet cap or thecoolant reservoir caps while the hybrid sys-tem and radiator are hot.
High temperature steam or coolant could spray out.
GS450h
GS300h