2015 Lexus IS250 coolant temperature

5068-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
●The needle of the engine coolant temperature gauge (P. 81) enters the red
zone or a loss of engine power is experienced. (For example, the vehicle
speed does not increase.)
●Steam comes out from under the hood.
Stop the vehicle in a safe place and tu rn off the air conditioning system, and
then stop the engine.
If you see steam:
Carefully lift the hood after the steam subsides.
If you do not see steam:
Carefully lift the hood.
After the engine 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.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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5078-2. Steps to take in an emergency
8
When trouble arises
IS350/250_U (OM53C50U)
The coolant level is satisfactory if it is
between the “FULL” and “LOW”
lines on the reservoir.Reservoir
“FULL”
“LOW”
Add coolant if necessary.
Water can be used in an emergency if
coolant is unavailable.
Start the engine and turn the air conditioning system on to check that the radi-
ator 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 oper ating by checking the fan sound and air flow.
If it is difficult to check th ese, turn the air conditioning system on and off repeatedly.
(The fans may not operate in freezing temperatures.)
If the fans are not operating:
Stop the engine immediately and contact your Lexus dealer.
If the fans are operating:
Have the vehicle inspected at the nearest Lexus dealer.
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5088-2. Steps to take in an emergency
IS350/250_U (OM53C50U)
CAUTION
■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 hood, do not open the hood until the steam
has subsided. The engine compartment may be very hot.
●Keep hands and clothing (especially a tie, a scarf or a muffler) away from the fans and
belts. Failure to do so may cause the hands or clothing to be caught, resulting in seri-
ous injury.
NOTICE
■When adding engine coolant
Add coolant slowly after the engine has cooled down sufficiently. Adding cool coolant
to a hot engine too quickly can cause damage to the engine.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreign matter (such as sand or dust etc.).
●Do not use any coolant additive.
●While the engine and radiator are hot, do not
loosen or remove the coolant reservoir cap
or radiator cap. (The radiator cap is located
under the engine cover.)
High temperature steam or coolant could
spray out.

570Alphabetical index
IS350/250_U (OM53C50U)
Emergency flashers ............................. 456
Engine .........................................................514ACCESSORY mode....................... 160
Compartment....................................... 413
Engine switch ........................................ 159
Hood ........................................................... 411
How to start the engine ................... 159
Identification number ........................ 513
If the engine will not start............... 496
Ignition switch (engine switch)..... 159
Overheating ........................................ 506
Engine coolant......................................... 417 Capacity .................................................. 516
Checking..................................................417
Preparing and checking before winter ................................... 260
Engine coolant temperature gauge ..........................................................81
Engine immobilizer system ................. 69
Engine oil ...................................................414 Capacity .................................................. 514
Checking................................................. 414
Preparing and checking before winter ................................... 260
Engine switch .......................................... 159
Enhanced VSC ..................................... 240
EPS (Electronic Power Steering) ..........241 Function ....................................................241
Warning light ....................................... 467
Event data recorder (EDR) ...................10 First-aid kit storage belt......................374
Flat tire ...................................................... 486
Floor mats....................................................26
Fluid
Automatic transmission .................... 517
Brake......................................................... 518
Washer ................................................... 422
Fog lights..................................................... 181 Replacing light bulbs ....................... 452
Switch ......................................................... 181
Wattage ................................................... 521
Footwell light .......................................... 368 Wattage ................................................... 521
Front passenger occupant classification system ............................ 47
Front personal lights ........................... 369 Wattage ................................................... 521
Front seats ................................................. 120 Adjustment..............................................120
Cleaning................................................. 399
Correct driving posture .................... 28
Driving position memory................. 123
Head restraints .....................................128
Power easy access system ............. 123
Seat heaters .......................................... 367
Seat position memory ....................... 123
Seat ventilators.................................... 367F