2015 LEXUS NX300h cooling

80 1-2. Hybrid system
NX300h_U_OM78007U ■
Sounds and vibrations spec ific to a hybrid vehicle
There may be no engine sound or vibration even though the vehicle is able to move with
the “READY” indicator is illuminated. For safety, make sure to shift the shift lever to P and
apply the parking brake when parked.
The following sounds or vibrat ions may occur when the hybrid system is operating and
are not a malfunction: ●
Motor sounds may be heard from the engine compartment. ●
Sounds may be heard from the hybrid battery (traction battery) behind the rear seats
when the hybrid system starts or stops. ●
Relay operating sounds such as a snap or soft clank will be emitted from the hybrid bat-
tery (traction battery), behind the rear seats, when the hybrid system is started or
stopped. ●
Sounds from the hybrid system may be heard when the back door is open. ●
Sounds may be heard from the transmission wh en the gasoline engine starts or stops,
when driving at low speeds, or during idling. ●
Engine sounds may be heard when accelerating sharply. ●
Sounds may be heard due to regenerative braking when the brake pedal is depressed
or as the accelerator pedal is released. ●
Vibration may be felt when the gasoline engine starts or stops.●
Cooling fan sounds may be heard from the air intake vents under the rear seats. ■
Vehicle proximity notification system
In the following cases, the ve hicle proximity notification system may be difficult for sur-
rounding people to hear. ●
In very noisy areas ●
In the wind or the rain
Also, as the vehicle proximity notification system is installed on the front of the vehicle, it
may be more difficult to hear from the re ar of the vehicle compared to the front.■
Maintenance, repair, re cycling, and disposal
Contact your Lexus dealer regarding maintenance, repair, recycling and disposal. Do
not dispose of the vehicle yourself. ■
Customization
Settings (e.g. on/off operation of the EV indicator) can be changed.
(Customizable features:  P. 6 3 3 )

82 1-2. Hybrid system
NX300h_U_OM78007U The cooling air intake and discharge
vents for the hybrid battery (traction
battery) are located under the rear
seats and between the rear seats and
deck board, respectively. If the air
intake vents are blocked, it could lead
to a reduction in hybrid battery (trac-
tion battery) output. The hybrid battery (traction battery)
output will not be reduced, even if the
space between the upper part of the air
discharge vents on the back of the rear
seat and deck board is blocked with lug-
gage, etc.
When a certain level of impact is detected by the impact sensor, the emergency
shut off system blocks the high voltage current and stops the fuel pump to mini-
mize the risk of electrocution and fuel leakage. If the emergency shut off system
activates, your vehicle will not restart. To restart the hybrid system, contact your
Lexus dealer.
A message is automatically displayed when a malfunction occurs in the hybrid
system or an improper operation is attempted.
If a warning message is shown on the
multi-information display, read the
message and follow the instructions.Hybrid battery (traction battery) air intake and discharge vents Air intake vents
Air discharge vents
Emergency shut off system
Hybrid warning message

304 4-5. Using the driving support systems
NX300h_U_OM78007U ■
Operation of the air conditioning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the air condi-
tioning system to enhance fuel efficiency. To improve air conditioning performance,
adjust the fan speed or turn off Eco drive mode. ■
Sport mode automatic deactivation
Sport mode is automatically deactivated if th e power switch is turned off after driving in
sport mode.

324 4-6. Driving tips
NX300h_U_OM78007UHybrid vehicle driving tips ◆ Using Eco drive mode
When using Eco drive mode, the torq ue corresponding to the accelerator
pedal depression amount can be generate d more smoothly than it is in normal
conditions. In addition, the operation of the air conditioning system (heat-
ing/cooling) will be minimized, improving the fuel economy. (  P. 3 0 3 )
◆ Use of Hybrid System Indicator
The Eco-friendly driving is possible by keeping the indicator needle of Hybrid
System Indicator within Eco area. (  P. 100)
◆ Shift lever operation
Shift the shift lever to D when stopped at a traffic light, or driving in heavy traf-
fic, etc. Shift the shift lever to P when parking. When using the N, there is no
positive effect on fuel consumption. In the N, the gasoline engine operates but
electricity cannot be generated. Also, wh en using the air conditioning system,
etc., the hybrid battery (traction battery) power is consumed.
◆ Accelerator pedal/brake pedal operation ●
Drive your vehicle smoothly. Avoid ab rupt acceleration and deceleration.
Gradual acceleration and deceleration will make more effective use of the
electric motor (traction motor) wi thout having to use gasoline engine
power. ●
Avoid repeated acceleration. Repeated acceleration consumes hybrid bat-
tery (traction battery) power, resulting in poor fuel consumption. Battery
power can be restored by driving with the accelerator pedal slightly
released.
◆ When braking
Make sure to operate the brakes gently and in a timely manner. A greater
amount of electrical energy can be regenerated when slowing down.For economical and ecological driving, pay attention to the following points:

434 6-1. Using the air conditioning system and defogger
NX300h_U_OM78007U ■
Option control screen
Select on the climate screen to display the option control screen. The
functions can be switched on and off.
Select to set cooling and de humidification function on/off
Adjust the temperature for driver and passenger seats separately (“DUAL”
mode) (  P. 4 3 5 )
Prevent ice from building up on the windshield and wiper blades
(  P. 4 3 6 )
Remove pollen from the air (Micro dust and pollen filter) (  P. 4 3 6 )■
Using the automatic mode
Press the “AUTO” button.
Adjust the temperature setting.
To stop the operation, press the “OFF” button.■
Automatic mode indicator
If the fan speed setting or air flow modes are operated, the automatic mode
indicator goes off. However, automati c mode for functions other than that
operated are maintained. 
Vehicles with a Lexus Display Audio
system 
Vehicles with a navigation system
Air conditioning controls 1
2
3
4
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2
3

438 6-1. Using the air conditioning system and defogger
NX300h_U_OM78007U ■
Fogging up of the windows ●
The windows will easily fog up when the humidity in the vehicle is high. Pressing “A/C”
button or selecting “A/C” will dehumidify th e air from the outlets and defog the wind-
shield effectively. ●
If you turn “A/C” off, the windows may fog up more easily. ●
The windows may fog up if the recirculated air mode is used. ■
Windshield fog detection function
When automatic mode is set, the humidity sensor (  P. 4 3 9 ) d e t e c t s f o g o n t h e w i n d -
shield and controls the air conditioning system to prevent fog. ■
Outside/recirculated air mode ●
When driving on dusty roads such as tunnels or in heavy traffic, set to
the recirculated air mode. This is effective in preventing outside air from entering the
vehicle interior. During cooling operation, setting the recirculated air mode will also
cool the vehicle interior effectively. ●
Outside/recirculated air mode may automati cally switch depending on the tempera-
ture setting or the inside temperature. ■
When the outside temperature is low
The dehumidification function may not operat e even when “A/C” is pressed or “A/C” is
selected. ■
Operation of the air conditioning system in Eco drive mode ●
In the Eco drive mode, the air conditioning sy stem is controlled as follows to prioritize
fuel efficiency
• Engine speed and compressor operation controlled to restrict heating/cooling
capacity
• Fan speed restricted when automatic mode is selected ●
To improve air conditioning performa nce, perform the following operations
• Adjust the fan speed
• Turn off Eco drive mode ■
Ventilation and air conditioning odors ●
To let fresh air in, set the air conditio ning system to the outside air mode.●
During use, various odors from inside and outside the vehicle may enter into and accu-
mulate in the air conditioning system. This may then cause odor to be emitted from the
vents. ●
To reduce potential odors from occurring:
• It is recommended that the air conditioning system be set to outside air mode prior
to turning the vehicle off.
• The start timing of the blower may be dela yed for a short period of time immediately
after the air conditioning system is started in automatic mode.■
Air conditioning filter
 P. 5 3 0 ■
Customization
Settings (e.g. A/C automatic mode switch operation) can be changed.
(Customizable features:  P. 6 3 9 )

4997-3. Do-it-yourself maintenance
7
Maintenance and care
NX300h_U_OM78007U WA R N I N G
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energized. To avoid death or serious injury, observe
the following precautions. ■
When working on the engine compartment ●
Make sure that the indicator on the power switch and the “READY” indicator are
both off. ●
Keep hands, clothing and tools away from the moving fan and engine drive belt.●
Be careful not to touch the engine, power control unit, radiator, exhaust manifold, etc.
right after driving as they may be hot. Oil and other fluids may also be hot. ●
Do not leave anything that may burn easily, such as paper and rags, in the engine
compartment. ●
Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flamma-
ble. ■
When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automatically start to
run if the air conditioning is on and/or the coolant temperature is high. (  P. 5 0 9 )■
Safety glasses
Wear safety glasses to prevent flying or fallin g material, fluid spray, etc. from getting in
your eyes.
NOTICE ■
If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive engine wear due to dirt
in the air.

502 7-3. Do-it-yourself maintenance
NX300h_U_OM78007UEngine compartment
■
12-volt battery
 P. 5 1 2Fuse box (  P. 5 3 4 )
Engine coolant reservoir
(  P. 5 0 8 )
Engine oil filler cap (  P. 505)
Power control unit coolant reservoir
(  P. 5 0 8 )
Brake fluid reservoir (  P. 5 1 0 ) Radiator (  P. 5 0 9 )
Condenser (  P. 5 0 9 )
Electric cooling fans
Engine oil level dipstick
(  P. 5 0 4 )
Wa s h e r f l u i d t a n k (  P. 5 1 1 )1
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