2015 LEXUS RX450h cooling

3553-2. Using the air conditio ning system and defogger
3
Interior features ■
Operation of the air conditioning system in Eco drive mode
In Eco drive mode, the air conditioning syst em 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 performanc e, perform the following operations:●
Adjust the fan speed●
Turn off Eco drive mode■
Customization
The air conditioning control of Eco drive mode can be changed to the same setting
as that used in normal drive mode.
(Customizable features  P. 825)■
Air conditioning system settings ●
When the “POWER” switch is turned on, the air conditioning system settings
will be set to those that were in use the last time the “POWER” switch was
turned off.●
Air conditioning system settings are memorized individually on each electronic
key, so the settings repr oduced will be specific to the key that is used.●
This feature is customizable at your Lexus dealer.■
Using automatic mode
Fan speed is adjusted automatically accord ing to the temperature setting and ambi-
ent conditions. As a result, the following may occur:
Immediately after the button is pressed, the fan may stop for a while until warm or
cool air is ready to flow.■
Using the system in recirculated air mode
The windows will fog up more easily if recirculated air mode is used for an extended
period.
■
Switching between outside air and recirculated air modes
Recirculated air mode or outside air mode may be automatically switched in accor-
dance with the temperature setting and the inside temperature.

3563-2. Using the air conditio ning system and defogger
■
When the outside temperature exceeds 75°F (24°C) and the air conditioning
system is on ●
In order to reduce the air conditioning power consumption, the air conditioning
system may switch to recirculated air mode automatically. This may also reduce
fuel consumption.●
Recirculated air mode is selected as a default mode when the “POWER” switch
is turned to ON mode.●
It is possible to switch to outside air mode at any time by pressing .■
Window defogger feature
Recirculated air mode may automatically switch to outside air mode in situations
where the windows need to be defogged.■
When outside air temperature is below 32  F (0  C)
The cooling and dehumidification fu nction may not operate even when
is
pressed.■
When the indicator light on goes off
Press to turn on the cooling and dehumi dification function again. There may
be a problem in the air conditioning system if the indicator light goes off again
shortly after the button is pressed. Have it inspected by your Lexus dealer.■
Ventilation and air conditioning odors ●
To let fresh air in, set the air conditioning system to the outside air mode.●
During use, various odors from inside and outside the vehicle may enter into
and accumulate in the air conditioning sy stem. 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 delayed for a short period of time
immediately after the air conditioning system is started in automatic mode.

6504-3. Do-it-yourself maintenance
CAUTIONThe engine compartment contains many mechanisms and fluids that may move sud-
denly, 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 fans 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 easi ly, such as paper and rags, in the engine
compartment.●
Do not smoke, cause sparks or expose an open flame to fuel. Fuel fumes are flam-
mable■
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 automati-
cally start to run if the air conditioning is on and/or the coolant temperature is high.
(  P. 6 6 1 )■
Safety glasses
Wear safety glasses to prevent flying or falling 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.

6544-3. Do-it-yourself maintenance
Engine compartment
Brake fluid reservoir
(  P. 6 6 2 )
Engine oil filler cap
(  P. 6 5 7 )
Engine oil level dipstick
(  P. 6 5 6 )
Power control unit coolant
reservoir (  P. 6 5 9 )
Fuse boxes (  P. 6 8 9 ) Engine coolant reservoir
(  P. 6 5 9 )
Condenser (  P. 6 6 1 )
Radiator (  P. 6 6 1 )
Electric cooling fans
Power control unit coolant
radiator (  P. 6 6 1 )
Washer fluid tank (  P. 663)

6604-3. Do-it-yourself maintenance
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. 788)
■
Coolant selection
Only use “Toyota Super Long Life Coolant” or 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 mixture of 50% coolant and
50% deionized water. (Minimum temperature: -31  F [-35  C])
Canada: “Toyota Super Long Life Coolant” 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 radiators, hoses, engine/power control unit coolant reservoir
caps, drain cock and water pump.
If you cannot find a leak, have your Lexus dealer test the cap and check for leaks in
the cooling systems.

6614-3. Do-it-yourself maintenance
4
Maintenance and care
Radiator and condenser
Check the radiator and condenser an d clear away any foreign objects.
If either of the above parts are extremely dirty or you are not sure of their
condition, have your vehicle checked by your Lexus dealer. CAUTION■
When the engine and hybrid system are hot
Do not remove the coolant reservoir 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 cooling. Be sure to read the antifreeze or coolant label.■
If you spill coolant
Be sure to wash it off with water to prevent damaging to parts or paint.
CAUTION■
When the hybrid system is hot
Do not touch the radiator or condenser as they may be hot and cause serious inju-
ries, such as burns.

6954-3. Do-it-yourself maintenance
4
Maintenance and care ■ Engine compartment (type B fuse box)
Fuse Ampere Circuit1
RR DEF 50 A Rear window defogger2
AIR SUS 50 A3
HEATER 50 A Air conditioning system4
ABS NO. 1 50 A Electronically controlled brake system5
RDI FAN NO. 1 40 A Electric cooling fans6
RDI FAN NO. 2 40 A Electric cooling fans7
H-LP CLN 30 A Headlight cleaner8
PBD 30 A Power back door9
HV R/B NO. 1 30 A PCU, IGCT NO. 2, IGCT NO. 3,
INV W/P
10
PD 50 A A/F, H-LP RH HI, H-LP LH LO, H-LP
RH LO, H-LP LH HI, HORN, S-
HORN
11
ABS NO. 2 50 A Electronically controlled brake system
12
HV R/B NO. 2 80 A ABS MAIN NO. 1, ABS MAIN NO.
2, A/C W/P, BATT FAN, OIL PMP

6984-3. Do-it-yourself maintenance
35
ECU-IG1 NO. 4 10 A Air conditioning system, rear window
defogger, electronically controlled
brake system, electric cooling fans36
BK/UP LP 7. 5 A Back-up lights37
ECU-IG1 NO. 5 15 A Air conditioning system38
ECU-IG1 NO. 6 10 A Head light cleaner, cruise control, air
conditioning system, Blind Spot Moni-
tor39
EFI NO. 2 10 A Multiport fuel injection system/
sequential multiport fuel injection sys-
tem40
F/ P M P 15 A Multiport fuel injection system/
sequential multiport fuel injection sys-
tem41
DEICER 25 A Windshield wipers and washer
42
STOP 7. 5 A Vehicle Proximity Notification System,
vehicle dynamics integrated manage-
ment, stop lights, multiport fuel injec-
tion system/sequential multiport fuel
injection system, shift lock control sys-
tem, starter system, cruise control43
TOW I N G BAT T 20 A44
TOW I N G 30 A Trailer lights45
FILTER 10 A
46
IG1 MAIN 30 A ECU-IG1 NO. 6, BK/UP LP, ECU-
IG1 NO. 5, ECU-IG1 NO. 4
47
H-LP RH HI 15 A Right-hand headlight (high beam)
48
H-LP LH HI 15 A Left-hand headlight (high beam)Fuse Ampere Circuit