2019 LEXUS GS300H coolant temperature

4757-2. Steps to take in an emergency
7
When trouble arises
GS450h_300h_OM_OM30F92E_(EE)
Indicates a malfunction in:
• The SRS airbag system; or • The seat belt pretensioner systemA buzzer also sounds.
 Have the vehicle inspected by any authorized Lexus retailer or Lexus authorized repairer, or any reliablerepairer.
Indicates a malfunction in:•The ABS; or• The brake assist system
A buzzer also sounds.  Immediately stop the vehicle in a safe place and contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
Indicates that the engine coolant temperature is too high
A buzzer also sounds.  P. 535
Indicates a malfunction in the vehicle’s charging system.  Immediately stop the vehicle in a safe place and contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer.
Warning messageDetails/Actions

535
7
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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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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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

587Alphabetical index
GS450h_300h_OM_OM30F92E_(EE)
Engine coolant temperature
gauge....................................................... 105
Engine oil..................................................406
Capacity ................................................ 550
Checking .............................................. 406
Oil level warning message ...........466
Oil pressure warning
message..............................................466
Preparing and checking
before winter .................................... 334
Engine switch ...........................................217
Auto power off function ...................219
Changing the power switch
modes ................................................... 218
If your vehicle has to be
stopped in an emergency..........453
Starting the hybrid system............... 217
EPS (Electric Power Steering)........ 325
Function .................................................. 325
Warning light .........................................461
Warning message.............................466
EV drive mode ....................................... 222
First-aid kit storage net....................... 375
Flat tire
Vehicles with spare tire ................. 498
Vehicles without spare tire .......... 509
Floor mats ................................................... 34
Fluid
Brake........................................................554
Hybrid transmission .........................553
Washer ...................................................... 411
Fog lights .................................................. 250
Replacing light bulbs ....................... 449
Switch ...................................................... 250
Follow me home system .................... 238
Footwell light .......................................... 366
Front air conditioning system .......... 346
Front fog lights ....................................... 250
Replacing light bulbs ....................... 449
Switch ...................................................... 250
Wattage ................................................. 449
Front personal lights............................ 367
Front position lights ............................. 237
Light switch............................................ 237
Replacing light bulbs ....................... 449
Welcome light illumination
control ................................................... 140
Front seats ................................................. 175
Adjustment ............................................. 175
Cleaning ................................................ 394
Correct driving posture.................... 36
Driving position memory ................ 178
Head restraints .....................................183
Power easy access system............. 178
Seat heaters.......................................... 362
Seat position memory ....................... 178
Seat ventilators ................................... 362
Front turn signal lights ..........................231
Replacing light bulbs ........... 443, 449
Turn signal lever................................... 231
Wattage .................................................558
F
*: Refer to the “NAVIGATION AND MULTIMEDIA
SYSTEM OWNER’S MANUAL”.