Page 348 of 492

3486-3. Do-it-yourself maintenance
AVALON_HV_U (01999-07002)■
Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
“MAX” line
“MIN” line
■Adding fluid
Make sure to check the fluid ty pe and prepare the necessary item.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking effi-
ciency. Use only newly opened brake fluid.
Brake fluid
1
2
Fluid type FMVSS No.116 DOT 3 or SAE J1703 brake fluid
Items Clean funnel
WARNING
■When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads
wear out or when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, there may be a serious problem. 
         
        
        
     
        
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3496-3. Do-it-yourself maintenance
6
Maintenance and care
AVALON_HV_U (01999-07002)
If any washer does not work or the
warning message appears on the
multi-information display, the
washer tank may be empty. Add
washer fluid.
Washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the hybrid system is hot or operating as
washer fluid contains alcohol and may catch fire if spilled on the engine etc.
NOTICE
■Do not use any fluid other than washer fluid 
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■ Diluting washer fluid
Dilute washer fluid with water as necessary. 
Refer to the freezing temperatures listed on the label of the washer fluid bot-
tle. 
         
        
        
     
        
        Page 350 of 492
3506-3. Do-it-yourself maintenance
AVALON_HV_U (01999-07002)
The 12-volt battery is located on
the right-hand side of luggage
compartment.
Pull the 12-volt battery cover while
pressing down on the tab.
Make sure that the 12-volt battery terminals are not corroded and that
there are no loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
12-volt batter y
Location
Removing the 12-volt battery cover
Exterior
1
2 
         
        
        
     
        
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3516-3. Do-it-yourself maintenance
6
Maintenance and care
AVALON_HV_U (01999-07002)
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flam-
mable and explosive. Therefore, observe the following precautions before
recharging:
●If recharging with the 12-volt battery installed on the vehicle, be sure to dis-
connect the ground cable.
● Make sure the power switch on the charger is off when connecting and dis-
connecting the charger cables to the 12-volt battery.
■ After recharging/reconnecting the 12-volt battery
●The hybrid system may not start. Follow the procedure below to initialize the
system.
Shift the shift lever to P.
Open and close any of the doors.
Restart the hybrid system.
● Unlocking the doors using the smart key system may not be possible imme-
diately after reconnecting the 12-volt battery. If this happens, use the wire-
less remote control or the mechanical key to lock/unlock the doors.
● Start the hybrid system with the power switch in ACCESSORY mode. The
hybrid system may not start when the power switch turned from off. How-
ever, the hybrid system will operat e normally from the second attempt.
● The power switch mode is recorded by the vehicle. If the 12-volt battery is
reconnected, the vehicle will return the power switch mode to the status it
was in before the 12-volt battery was disconnected. Make sure to turn off
the power switch before disconnect the 12-volt battery. Take extra care
when connecting the 12-volt battery if the power switch mode prior to dis-
charge is unknown.
If the system will not start even after multiple attempts at all methods above,
contact your Toyota dealer.
1
2
3 
         
        
        
     
        
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3526-3. Do-it-yourself maintenance
AVALON_HV_U (01999-07002)
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid and may
produce hydrogen gas which is flammable and explosive. To reduce the risk
of death or serious injury, take the following precautions while working on or
near the 12-volt battery:
●Do not cause sparks by touching the 12-volt battery terminals with tools.
● Do not smoke or light a match near the 12-volt battery.
● Avoid contact with eyes, skin and clothes.
● Never inhale or swallow electrolyte.
● Wear protective safety glasses when working near the 12-volt battery.
● Keep children away from the 12-volt battery.
■ Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charge the 12-
volt battery in a garage or closed room where there is insufficient ventila-
tion.
■ How to recharge th e 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may explode if
charged at a quicker rate. 
         
        
        
     
        
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3536-3. Do-it-yourself maintenance
6
Maintenance and care
AVALON_HV_U (01999-07002)
WARNING
■Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immedi-
ate medical attention. If possible, continue to apply water with a sponge or
cloth while traveling to the nearest medical facility.
● If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical
attention immediately.
● If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the cloth-
ing and follow the procedure above if necessary.
● If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention
immediately.
■ When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause
gas (hydrogen) to enter the passenger compartment, causing a fire or
explosion.
For replacement of the 12-volt battery, contact your Toyota dealer.
NOTICE
■When recharging the 12-volt battery
Never recharge the 12-volt battery while the hybrid system is operating.
Also, be sure all accessories are turned off. 
         
        
        
     
        
        Page 354 of 492
3546-3. Do-it-yourself maintenance
AVALON_HV_U (01999-07002)
Check if the treadwear indicators are showing on the tires. Also check
the tires for uneven wear, such as  excessive wear on one side of the
tread.
Check the spare tire condition  and pressure if not rotated.
New tread
Worn tread
Treadwear indicator
The location of treadwear indicators is shown by a “TWI” or “ ” mark,
etc., molded into the sidewall of each tire. 
Replace the tires if the treadwear indicators are showing on a tire.
Rotate the tires in the order
shown.
To equalize tire wear and extend
tire life, Toyota recommends that
tire rotation is carried out at the
same interval as tire inspection.
Do not fail to initialize the tire
pressure warning system after
tire rotation.
Tires
Replace or rotate tires in acco rdance with maintenance sched-
ules and treadwear.
Checking tires
Tire rotation
1
2
3
Front 
         
        
        
     
        
        Page 355 of 492

3556-3. Do-it-yourself maintenance
6
Maintenance and care
AVALON_HV_U (01999-07002)
Your vehicle is equipped with a tire pressure warning system that uses
tire pressure warning valves and tr ansmitters to detect low tire infla-
tion pressure before serious problems arise. 
● If the tire pressure drops below a  predetermined level, the driver is
warned by a screen display and a warning light. ( P. 399)
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pr essure warning system must be
initialized. Have tire pressure warning valve and transmitter ID
codes registered by your Toyota dealer. ( P. 357)
◆Initializing the tire pressure warning system
■The tire pressure warning system  must be initialized in the fol-
lowing circumstances:
● When changing the tire size.
● When the tire inflation pressure is changed such as when chang-
ing traveling speed or load weight.
● When rotating the tires.
When the tire pressure warning system is initialized,  the current tire
inflation pressure is set as the benchmark pressure.
Tire pressure warning system
● The tire pressure detected by the
tire pressure warning system can
be displayed on the multi-informa-
tion display.