2018 Lexus ES300h radiator cap

447
ES300h_OM_OM33D45U_(U)7-3. Do-it-yourself maintenance
7
Maintenance and care
Engine compartment
■12-volt battery
→
P. 457
Washer fluid tank ( →P. 456)
Fuse boxes (→ P. 480)
Power control unit coolant
reservoir ( →P. 453)
Engine oil level dipstick (→P. 449)
Engine oil filler cap (→ P. 450)Engine coolant reservoir
(→P. 453)
Brake fluid reservoir ( →P. 455)
Power control unit coolant
radiator (→ P. 454)
Electric cooling fans
Condenser ( →P. 454)
Engine coolant radiator (→P. 454)1
2
3
4
5
6
7
8
9
10
11

ES300h_OM_OM33D45U_(U)
4537-3. Do-it-yourself maintenance
7
Maintenance and care
The coolant level is satisfactory if it is between the “FULL” and “LOW” lines on
the reservoir when the hybrid system is cold.
■Engine coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( →P. 531)
■Power control unit coolant reservoir
Reservoir cap
“FULL” line
“LOW” line
If the level is on or below the “LOW”
line, add coolant up to the “FULL”
line. ( →P. 531)
■Coolant selection
Only use “Toyota Super Long Life Coolant” or a similar high quality ethylene glycol
based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid
organic acid technology.
U.S.A.:
“Toyota Super Long Life Coolant” is a mixt ure of 50% coolant and 50% deionized water.
(Minimum temperature: -31 °F [-35 °C])
Canada:
“Toyota Super Long Life Cool ant” is a mixture of 55% coolant and 45% deionized water.
(Minimum temperature: -44° F [-42°C])
For more details about coolant, contact your Lexus dealer.
■If the coolant level drops within a short time of replenishing
Visually check the radiator, hoses, engine c oolant reservoir cap, power control unit cool-
ant reservoir cap, drain cock and water pump.
If you cannot find a leak, have your Lexus de aler test the cap and check for leaks in the
cooling system.
Coolant
1
2
3
1
2
3

454
ES300h_OM_OM33D45U_(U)7-3. Do-it-yourself maintenance
Check the radiator and condenser an
d clear away any foreign objects.
If either of the above parts is extremely dirty or you are not sure of their condi-
tion, have your vehicle inspected by your Lexus dealer.
WARNING
■When the hybrid system is hot
Do not remove the engine coolant reservoi r cap, power control unit coolant reservoir
cap, or the radiator cap.
The cooling system may be under pressure and may spray hot coolant if the cap is
removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of water and
antifreeze must be used to provide proper lubrication, corrosion protection and cool-
ing. Be sure to read the antifreeze or coolant label.
■If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
Radiator and condenser
WARNING
■When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause serious injuries,
such as burns.

531
ES300h_OM_OM33D45U_(U)8-2. Steps to take in an emergency
8
When trouble arises
If your vehicle overheats
■If the needle of the engine coolant temperature gauge enters the red zone
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 your Lexus
dealer.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.Reservoir
“FULL”
“LOW”
Radiator cap
The following may indicate that your vehicle is overheating.
●The needle of the engine coolant temperature gauge ( →P. 86) enters the
red zone or a loss of hybrid system po wer is experienced. (For example, the
vehicle speed does not increase.)
●“Hybrid System Overheated” is shown on the multi-information display.
●Steam comes out from under the hood.
Correction procedures
1
2
3
1
2
4
1
2
3
4

5348-2. Steps to take in an emergency
ES300h_OM_OM33D45U_(U)
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, or
the 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) ge tting caught, resulting in serious injury.
●Do not loosen the radiator cap or the c oolant reservoir cap while the hybrid system
and radiator are hot. High temperature steam or coolant could spray out.
NOTICE
■When adding engine/power control unit coolant
Add coolant slowly after the hybrid system has cooled down sufficiently. Adding cool
coolant to a hot hybrid system too quickly can cause damage to the hybrid system.
■To prevent damage to the cooling system
Observe the following precautions:
●Avoid contaminating the coolant with foreig n matter (such as sand or dust etc.).
●Do not use any coolant additive.

598Alphabetical index
ES300h_OM_OM33D45U_(U)
Parking assist sensors (intuitive parking assist) .................. 237
Parking brake Operation ................................................. 181
Parking brake engaged warning buzzer .................................. 181
Parking lights Light switch ............................................ 182
Replacing light bulbs ........................492
PCS (Pre-Collision System) Function ................................................. 205
Warning light ...................................... 504
Personal lights........................................ 397
Power control unit .................................... 71
Power control unit coolant Capacity .................................................543
Checking................................................453
Preparing and checking before winter ................................... 280
Radiator ..................................................454
Power easy access system ................ 130
Power outlets ......................................... 406
Power steering (Electric Power
Steering system) ................................ 273 Warning light ...................................... 504
Power switch ........................................... 168 Power trunk opener and closer .........114
Power windows
Door lock linked window operation ...........................146
Jam protection function....................145
Operation................................................145
Window lock switch ..........................145
Pre-Collision System (PCS) Function ..................................................205
Warning light .......................................504
Radar cruise control (dynamic radar cruise control).........................225
Radiator.................................................... 454
Radio
*........................................................ 312
RCTA (Rear Cross Traffic Alert).........................................264
Rear personal lights .............................397
Rear side marker lights Light switch.............................................182
Replacing light bulbs ....................... 492
Rear door sunshades.......................... 408
Rear sunshade Operation............................................. 408
Reverse operation feature ............409
P
R