air condition LEXUS RX300H 2017 Workshop Manual

4897-3. Do-it-yourself maintenance
7
Maintenance and care
RC300h_EE(OM24740E)
■Situations in which the tire pressure warning system may not operate properly
●In the following cases, the tire pressure warning system may not operate properly.
• If non-genuine Lexus wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equipment) tire. • A tire has been replaced with a tire that is not of the specified size.• Tire chains etc. are equipped.
• An auxiliary-supported run-flat tire is equipped. • If a window tint that affects the radio wave signals is installed.• If there is a lot of snow or ice on the vehi cle, particularly around the wheels or wheel
housings. • If the tire inflation pressure is extr emely higher than the specified level. • If tires not equipped with tire pressure warning valves and transmitters are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, large display, air- port or other facility that generates st rong radio waves or electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless communication deviceIf tire position information is not correctly displayed due to the radio wave conditions,
the display may be corrected by driving and changing the radio wave conditions.
●When the vehicle is parked, the time taken for the warning to start or go off could be extended.
●When tire inflation pressure declines rapi dly for example when a tire has burst, the warning may not function.
■The initialization operation
●Make sure to carry out initialization af ter adjusting the tire inflation pressure. Also, make sure the tires are cold before carry ing out initialization or tire inflation pres-
sure adjustment.
●If you have accidentally turned the power switch off during initialization, it is not neces- sary to press the reset switch again as init ialization will restart automatically when the
power switch has been turned to ON mode for the next time.
●If you accidentally press the reset switch when initialization is not necessary, adjust the tire inflation pressure to the specified leve l when the tires are cold, and conduct initial-
ization again.
■Warning performance of the tire pressure warning system
The warning of the tire pressure warning syst em will change in accordance with the con-
ditions under which it was initialized. For this reason, the system may give a warning even if the tire pressure does not reach a low enough level, or if the pressure is higher than the pressure that was adjusted to when the system was initialized.

4987-3. Do-it-yourself maintenance
RC300h_EE(OM24740E)
NOTICE
■Repairing or replacing tires, wheels, tire pressure warning valves, transmitters and tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning valves and
transmitters, contact any authorized Lexus de aler or repairer, or another duly quali- fied and equipped professional as the tire pressure warning valves and transmitters may be damaged if not handled correctly.
●Make sure to install the tire valve caps. If the tire valve caps are not installed, water could enter the tire pressure warning valv es and the tire pressure warning valves could be bound.
●When replacing tire valve caps, do not use tire valve caps other than those specified.The cap may become stuck.
■To avoid damage to the tire pressure warning valves and transmitters
When a tire is repaired with liquid sealants, the tire pressure warning valve and trans- mitter may not operate properly. If a liquid sealant is used, contact any authorizedLexus dealer or repairer, or another duly qu alified and equipped professional or other
qualified service shop as soon as possible. After use of liquid sealant, make sure to replace the tire pressure warning valve and transmitter when repairing or replacing the tire. ( P. 486)
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes. These conditions may cause losses in tire inflation pressure, reducing the cushioning
ability of the tires. In addition, driving on rough roads may cause damage to the tires themselves, as well as the vehicle’s wheels and body.
■Low profile tires
Low profile tires may cause greater damage than usual to the tire wheel when sustain- ing impact from the road surface. Therefore, pay attention to the following:
●Be sure to use proper tire inflation pressu re. If tires are under-inflated, they may be
damaged more severely.
●Avoid potholes, uneven pavement, curbs an d other road hazards. Failure to do so may lead to severe tire and wheel damage.
■If tire inflation pressure of ea ch tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

5067-3. Do-it-yourself maintenance
RC300h_EE(OM24740E)
WARNING
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. If the tires are not properly inflated, the following conditions may occur which could
lead to an accident resulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of tire damage while driving (due to road hazards, expansion joints, sharp edges in the road, etc.)
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on. If a valve cap is not installed, dirt or moisture may get into the valve and cause an airleak, resulting in decrease d tire inflation pressure.

5097-3. Do-it-yourself maintenance
7
Maintenance and care
RC300h_EE(OM24740E)
Turn the power switch off.
Open the glove box. Lift up the side
with the stay, disconnect the stay
tabs and remove the partition by
pulling horizontally.
Press the tabs and remove the filter
cover.
Press the tabs and remove the filter
case.
Air conditioning filter
The air conditioning filter must be changed regularly to maintain air condi-
tioning efficiency.
Removal method
1
2
3
4

5107-3. Do-it-yourself maintenance
RC300h_EE(OM24740E)
Remove the air conditioning filter
from the filter case and replace it
with a new one.
The “ UP” marks shown on the filter
and the filter case should be pointing up.
■Checking interval
Inspect and replace the air conditioning filt er according to the maintenance schedule. In dusty areas or areas with heavy traffic fl ow, early replacement may be required. (For
scheduled maintenance information, please refer to the “Lexus Service Booklet” or “Lexus Warranty Booklet”.)
■If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
■Air conditioning filter with deodorizing function
When fragrances are placed in your vehicle, the deodorizing effect may become signifi-
cantly weakened in a short period.
When an air conditioning odor comes out cont inuously, replace the air conditioning filter.
5
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the system.

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

5408-2. Steps to take in an emergency
RC300h_EE(OM24740E)
*1: Open door warning buzzer:
 P. 544
*2: Seat belt warning buzzer:
The seat belt warning buzzer sounds to al ert the driver, front passenger and rear pas- sengers that his or her seat belt is not fastened. The buzzer sounds for 30 seconds
after the vehicle reaches a speed of 20 km/h (12 mph). Then, if the seat belt is still unfastened, the buzzer will sound in a different tone for 90 more seconds.
■Front passenger detection sensor, seat belt reminder and warning buzzer
●If luggage is placed on a front passenger seat, the front passenger detection sensormay cause the warning light to flash and the warning buzzer to sound even if a passen-
ger is not sitting in the seat.
●If a cushion is placed on the seat, the sensor may not detect a passenger, and the warn- ing light may not operate properly.
■If the malfunction indicator lamp comes on while driving
The malfunction indicator lamp will come on if the fuel tank becomes completely empty. If the fuel tank is empty, refuel the vehicle immediately. The malfunction indicator lamp
will go off after several trips.
If the malfunction indicator lamp does not go off, contact any authorized Lexus dealer or repairer, or another duly qualified and eq uipped professional as soon as possible.
■Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage temporarily drops, the electric power steering system warning light may come on and the warning buzzer
may sound.
■When the tire pressure warning light comes on
Carry out the following procedure after the tire temperature has lowered sufficiently.
●Check the tire inflation pressure and adjust to the appropriate level.
●If the warning light does not go out even afte r several minutes, check that the tire infla- tion pressure is at the specifie d level and carry out initialization.
The warning light may come on again if the above operations are conducted without first allowing the tire temperature to lower sufficiently.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such as natural air leaks and tire inflation pressure changes caused by temperature. In this case, adjustingthe tire inflation pressure will turn off the warning light (after a few minutes).
■When a tire is replaced with the spare tire (if equipped)
The spare tire is not equipped with a tire pre ssure warning valve and transmitter. If a tire
goes flat, the tire pressure warning light will no t turn off even though the flat tire has been replaced with the spare tire.
■Conditions that the tire pressure warning system may not function properly
P. 489

5488-2. Steps to take in an emergency
RC300h_EE(OM24740E)
(If equipped)
Indicates that the dynamic radar cruise control system is
unable to judge vehicle-to-vehicle distance A buzzer also sounds. Turn off snow mode.
If the windshield wipers are on, turn them off or set them to a mode other than AUTO or high speedwiper operation.
(If equipped)
Indicates that the LDA (Lane Departure Alert) system issuspended (The camera sensor temperature is higher
than the operation temperature range) A buzzer also sounds. Restart the LDA after driving for a while.
(If equipped)
Indicates that a Blind Spot Monitor sensor or the sur- rounding area on the rear bumper is dirty or covered
with snow, ice, etc. or that a sensor is misaligned A buzzer also sounds. Clean off the dirt, snow, ice, etc. and drive the vehi-
cle with the operation conditions of the BSM func- tion ( P. 327) satisfied for approximately 10
minutes. If the warning message does not disappear, the sensor may be misaligned. Have the vehicleinspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Indicates a malfunction in:• The cruise control system; or
• The dynamic radar cruise control system (if equipped) Press the “ON/OFF” button once to deactivate thesystem, and then press the button again to reactivate
the system. A buzzer also sounds. Have the vehicle inspected by any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional.
Warning messageDetails/Actions

5518-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
Indicates that the windows are not fully closed (with the
power switch off, and the driver’s door open) A buzzer also sounds. Close all the windows.
(If equipped)
Indicates that the windows and the moon roof are not fully closed (with the power switch off, and the driver’s
door open) A buzzer also sounds. Close all the windows and the moon roof.
Indicates a malfunction in the brake override 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 engine oil level is low This message may appear if the vehicle is stopped on a
slope. Move the vehicle to a level surface and check to see if the message disappears.A buzzer also sounds.
 Check the level of engine oil, and add if necessary.
Indicates that the hybrid system has overheated This message may be displayed when driving undersevere operating conditions. (For example, when driv-
ing up a long steep hill.) A buzzer also sounds.
 Stop and check. (P. 587)
Warning messageDetails/Actions
(Flashes)
(Flashes)

5538-2. Steps to take in an emergency
8
When trouble arises
RC300h_EE(OM24740E)
Indicates a malfunction in the tire pressure warning sys- tem
 Stop the vehicle in a safe place and turn the power switch off then on again.If the tire pressure warning indicator flashes for 1
minute then illuminates, th ere is a malfunction in the system. Have the vehicle inspected by any autho-rized Lexus dealer or repairer, or another duly qual-
ified and equipped professional.
Indicates that the tire position information cannot be rec- ognized Drive for a short while and check if the display
updates. If the radio wave conditions improve, the displaymay return to normal. If the tire pressure is still not
displayed after driving for several minutes, stop the vehicle in a safe place, turn the power switch offthen on again, and start driving.
If the tire pressure is still not displayed even after repeating this process several times, have the vehi-cle inspected by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Maintenance of the hybrid battery (traction battery)
cooling component is required The filter may be clogged, the air intake vent may beblocked or there may be a gap in the duct
 Have maintenance performed on the hybrid battery (traction battery) cooling component by any autho-rized Lexus dealer or repairer, or another duly qual-
ified and equipped professional.
Indicates that the washer fluid level is low  Add washer fluid.
Indicates that remaining fuel is approximately 10 L (2.6 gal., 2.2 Imp. gal.) or less Refuel the vehicle.
Warning messageDetails/Actions