2015 Lexus IS300h coolant temperature

5318-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
Indicates that the hybrid battery (traction battery) is lowA buzzer also sounds.
→ When stopping the vehicle for a long period of time,
shift the shift lever to P. The hybrid battery (traction
battery) cannot be charged with the shift lever in N.
Indicates a malfunction in the EPS (Electric Power Steer-
ing) 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 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. 5 7 1
Wa r n i n g m e s s a g eDetails/Actions
(Flashes)
(Flashes)

5718-2. Steps to take in an emergency
8
When trouble arises
IS300h_EE(OM53D56E)
●The needle of the engine coolant temperature gauge (→P. 109) enters the
red zone or a loss of hybrid system power is experienced. (For example, the
vehicle speed does not increase.)
●“Hybrid System Overheat” 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
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, or
another duly qualified and
equipped professional.
The coolant level is satisfactory if
it is between the “FULL” and
“LOW” lines on the reservoir.
Reservoir
“FULL”
“LOW”
If your vehicle overheats
The following may indicate that your vehicle is overheating.
Correction procedures
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5728-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
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 air conditioning system is turned on immediately after a
cold start. Confirm that the fans are operating by checking the fan sound and air
flow. If it is difficult to check these, 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 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.
■If “Hybrid System Overheat” is shown on the multi-information displayStop 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.
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5748-2. Steps to take in an emergency
IS300h_EE(OM53D56E)
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.
●After the hybrid system has been turned off, check that the “READY” indicator is off.
When the hybrid system 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 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.
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.
●Do not loosen the coolant reservoir caps or
water filler cap while the hybrid system and
radiator are hot.
High temperature steam or coolant could
spray out.

613Alphabetical index
IS300h_EE(OM53D56E)
If you have a flat tire ............. 545, 559
If you think something is wrong...............................................520
If your vehicle becomes stuck..... 575
If your vehicle has to be stopped in an emergency........... 513
If your vehicle needs to be towed...............................................514
If your vehicle overheats ..................571
Emergency brake signal .................... 297
Emergency flashers .............................. 512
Emergency tire puncture
repair kit ................................................545
Energy monitor......................................... 121
Engine....................................................... 580 ACCESSORY mode ....................... 213
Compartment......................................455
Engine switch......................................... 212
Hood ........................................................453
How to start the hybrid
system .................................................... 212
Identification number ....................... 579
Ignition switch (power switch)................................... 212
Overheating ...........................................571
Power switch ......................................... 212 Engine coolant....................................... 460
Capacity.................................................583
Checking ............................................... 460
Preparing and checking
before winter.....................................322
Engine coolant temperature
gauge ...................................................... 109
Engine oil ................................................. 456
Capacity...................................................581
Checking ............................................... 456
Preparing and checking before winter.....................................322
Engine oil maintenance data ........... 458
Engine switch ........................................... 212
EPS (Electric Power Steering) ....... 296 Function.................................................. 296
Warning light........................................522
EV drive mode......................................... 217
EV indicator ............................................... 117