2017 LEXUS RC300H coolant

4797-3. Do-it-yourself maintenance
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Maintenance and care
RC300h_EE(OM24740E)
■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 hybridorganic acid technology.
“Toyota Super Long Life Coolant” is a mixt ure of 50% coolant and 50% deionized water. (Minimum temperature: -35 C [-31F])
For more details about coolant, contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
■If the coolant level drops within a short time of replenishing
Visually check the radiators, hoses, engine /power control unit coolant reservoir caps,
drain cock and water pump. If you cannot find a leak, have any authorized Lexus dealer or repairer, or another dulyqualified and equipped professional, test the cap and check for leaks in the cooling sys-
tem.
WARNING
■When the hybrid system is hot
Do not remove the engine/power control unit coolant reservoir caps or water filler cap. ( P. 590)
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.

5368-2. Steps to take in an emergency
RC300h_EE(OM24740E)
●Fluid leaks under the vehicle.
(Water dripping from the air conditioning after use is normal.)
●Flat-looking tires or uneven tire wear
●Engine coolant temperature gauge continually points higher than normal.
●Changes in exhaust sound
●Excessive tire squeal when cornering
●Strange noises related to the suspension system
●Pinging or other noises related to the hybrid system
●Engine missing, stumbling or running roughly
●Appreciable loss of power
●Vehicle pulls heavily to one side when braking
●Vehicle pulls heavily to one side when driving on a level road
●Loss of brake effectiveness, spongy fe eling, pedal almost touches the floor
If you think something is wrong
If you notice any of the following symptoms, your vehicle probably needs
adjustment or repair. Contact any authorized Lexus dealer or repairer, or
another duly qualified an d equipped professional as soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms

5478-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
Indicates that the vehicle is being driven at 5 km/h (3 mph) or more with the parking brake still engaged
A buzzer also sounds.  Release the parking brake.
Indicates a malfunction in: • The SRS airbag system; or• The seat belt pretensioner system
A buzzer also sounds.  Have the vehicle inspected by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Indicates a malfunction in: •The ABS; or• The brake assist system
A buzzer also sounds.  Have the vehicle inspected by any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional.
Indicates that the engine coolant temperature is too high
A buzzer also sounds.  P. 587
(If equipped)
Indicates that the radar sensor is dirty or covered with ice
A buzzer also sounds.  Clean the sensor.
Warning messageDetails/Actions
(Flashes)

5878-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
●The hybrid system coolant temperature gauge (P. 115) is in the red zone or
a loss of hybrid system power is experi enced. (For example, the vehicle speed
does not increase.)
●“Engine Coolant High Temperature” or “Hybrid System Overheat Output
Power is limited” 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 High Temperature” 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 radiator core (radi-
ator) for any leaks.
Radiator
Cooling fans
If a large amount of coolant leaks,
immediately contact any autho- rized Lexus dealer or repairer, oranother duly qualified and
equipped professional.
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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5888-2. Steps to take in an emergency
RC300h_EE(OM24740E)
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 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 ai r 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 fan may not operate in freezing temperatures.)
If the fans are not operating:
Stop the hybrid system immediately and contact any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional.
If the fans are operating:
Have the vehicle inspected at the nearest authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
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5898-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
■If “Hybrid System Overheat Output Power is limited” 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 dealer or repairer, or
another duly qualified and
equipped professional.
The coolant level is satisfactory if
it is between the “F” and “L” lines
on the reservoir.
Reservoir
“F”
“L”
Add coolant if necessary.
Water can be used in an emergency
if coolant is unavailable.
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5908-2. Steps to take in an emergency
RC300h_EE(OM24740E)
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 dealer or
repairer, or another duly qualified and equipped professional.
If the message is not displayed:
Have the vehicle inspected at the nearest authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
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 “READY” indicator is off.
When the hybrid system operating, the ga soline engine may automatically start, or the cooling fan may suddenly operate even if the gasoline engine stops. Do not touchor approach rotating parts such as the belt and fan, which may lead to fingers or
clothing (especially a tie, a scarf or a mu ffler) getting caught, resulting in serious injury.
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●Do not loosen the coolant reservoir caps orradiator cap while the hybrid system and radi-
ator are hot. High temperature steam or coolant couldspray out.

5918-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
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 foreign matter (such as sand or dust etc.).
●Do not use any coolant additive.