2021 TOYOTA AVALON HYBRID ECU

811-3. Hybrid system
1
For safety and security
■If a warning light comes on, a warning message is displayed, or the 12-
volt battery is disconnected
The hybrid system may not start. In this case, try to start the system again. If
the “READY” indicator does not come on, contact your Toyota dealer.
■Running out of fuel
When the vehicle has run out of fuel and the hybrid system cannot be started,
refuel the vehicle with at least enough gasoline to make the low fuel level
warning light (P. 458) go off. If there is only a small amount of fuel, the
hybrid system may not be able to start. (The standard amount of fuel is about
2.3 gal. [8.8 L, 1.9 Imp. gal.] when the vehicle is on a level surface. This value
may vary when the vehicle is on a slope. Add extra fuel when the vehicle is
inclined.)
■Electromagnetic waves
●High voltage parts and cables on hybrid vehicles incorporate electromag-
netic shielding, and therefore emit approximately the same amount of elec-
tromagnetic waves as conventional gasoline powered vehicles or home
electronic appliances.
●Your vehicle may cause sound interference in some third party-produced
radio parts.
■Hybrid battery (traction battery)
The hybrid battery (traction battery) has a limited service life. The lifespan of
the hybrid battery (traction battery) can change in accordance with driving
style and driving conditions.
■Starting the hybrid system in an extremely cold environment
When the hybrid battery (traction battery) is extremely cold (below approxi-
mately -22°F [-30°C]) under the influence of the outside temperature, it may
not be possible to start the hybrid system. In this case, try to start the hybrid
system again after the temperature of the hybrid battery (traction battery)
increases due to the outside temperature increase etc.

831-3. Hybrid system
1
For safety and security
WARNING
■Road accident cautions
Observe the following precautions to reduce the risk of death or serious
injury:
●Pull your vehicle off the road, apply the parking brake, shift the shift lever
to P, and turn the hybrid system off.
●Do not touch the high voltage parts, cables and connectors.
●If electric wires are exposed inside or outside your vehicle, an electric
shock may occur. Never touch exposed electric wires.
●If a fire occurs in the hybrid vehicle, leave the vehicle as soon as possible.
Never use a fire extinguisher that is not meant for electric fires. Using even
a small amount of water may be dangerous.
●If your vehicle needs to be towed, do so with front wheels raised. If the
wheels connected to the electric motor (traction motor) are on the ground
when towing, the motor may continue to generate electricity. This may
cause a fire. (P. 451)
●Carefully inspect the ground under the vehicle. If you find that liquid has
leaked onto the ground, the fuel system may have been damaged. Leave
the vehicle as soon as possible.
●If electrolyte is leaking from the hybrid battery (traction battery), do not
approach the vehicle.
Even in the unlikely event that the hybrid battery (traction battery) is dam-
aged, the internal construction of the battery will prevent a large amount
of electrolyte from leaking out. However, any electrolyte that does leak out
will give off a vapor. This vapor is an irritant to skin and eyes and could
cause acute poisoning if inhaled.
●Do not touch the hybrid battery (traction battery) if liquid is leaking from or
adhering to it. If electrolyte (carbonic-based organic electrolyte) from the
hybrid battery (traction battery) comes into contact with the eyes or skin, it
could cause blindness or skin wounds. In the unlikely event that it comes
into contact with the eyes or skin, wash it off immediately with a large
amount of water, and seek immediate medical attention.
●Do not bring burning or high-temperature items close to the electrolyte.
The electrolyte may ignite and cause a fire.

851-3. Hybrid system
1
For safety and security
NOTICE
■Hybrid battery (traction battery) air intake vent
●Make sure not to block the air intake vent with anything, such as a seat
cover, plastic cover, or luggage. The hybrid battery (traction battery) may
overheat and be damaged.
●When dust etc. has accumulated in the air intake vent, clean it with a vac-
uum cleaner to prevent the vent from clogging.
●Do not get water or foreign materials in the air intake vent as this may
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5c0003000b00570055004400460057004c0052005100030045[attery).
●Do not carry large amounts of water such as water cooler bottles in the
vehicle. If water spills onto the hybrid battery (traction battery), the battery
may be damaged. Have the vehicle inspected by your Toyota dealer.
●There is a filter installed to the air intake vent. When the filter remains
noticeably dirty even after cleaning the air intake vent, filter cleaning or
replacement is recommended. When cleaning the filter, refer to P. 434.

861-4. Theft deterrent system
The indicator light flashes after
the power switch has been turned
off to indicate that the system is
operating.
The indicator light stops flashing
after the power switch has been
turned to ACCESSORY or ON
mode to indicate that the system
has been canceled.
■System maintenance
The vehicle has a maintenance-free type immobilizer system.
■Conditions that may cause the system to malfunction
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4400030050004800570044004f004f004c0046000300520045[ject
●If the key is in close proximity to or touching a key to the security system
(key with a built-in transponder chip) of another vehicle
Immobilizer system
The vehicle’s keys have built-in transponder chips that prevent
the hybrid system from starting if a key has not been previously
registered in the vehicle’s on-board computer.
Never leave the keys inside the vehicle when you leave the vehi-
cle.
This system is designed to help prevent vehicle theft but does
not guarantee absolute security against all vehicle thefts.

871-4. Theft deterrent system
1
For safety and security
■Certifications for the immobilizer system
For vehicles sold in the U.S.A.
For vehicles sold in Canada
WARNING
■Certifications for the engine immobilizer system
Changes or modifications not expressly approved by the party responsible
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5200530048005500440057004800030057004b004800030048[quipment.
NOTICE
■To ensure the system operates correctly
Do not modify or remove the system. If modified or removed, the proper
operation of the system cannot be guaranteed.

891-4. Theft deterrent system
1
For safety and security
■System maintenance
The vehicle has a maintenance-free type alarm system.
■Items to check before locking the vehicle
To prevent unexpected triggering of the alarm and vehicle theft, make sure of
the following:
●Nobody is in the vehicle.
●The windows and moon roof (if equipped) are closed before the alarm is set.
●No valuables or other personal items are left in the vehicle.
■Triggering of the alarm
The alarm may be triggered in the following situations:
(Stopping the alarm deactivates the alarm system.)
●The trunk is opened using the mechani-
cal key.
●A person inside the vehicle opens a door
or the trunk or hood, or unlocks the vehi-
cle.
●The 12-volt battery is recharged or
replaced when the vehicle is locked.
(P. 490)

962. Instrument cluster
*2“BSM” indicator
(P. 276)*2“SPORT” indicator
(P. 321)
*2“RCTA” indicator
(P. 276)*2“ECO MODE” indicator
(P. 321)
*5, 6BSM (Blind Spot Moni-
tor) outside rear view
mirror indicators
(P. 276)*2EV drive mode indicator
(P. 202)
*1, 7“AIR BAG
ON/OFF”
indicator
(P. 48)*2
EV indicator (P. 77)
*7Security indicator
(P. 86, 88)“READY” indicator
(P. 196)
*2
(if equipped)
Intuitive parking assist
indicator (P. 292)*2, 8
Low outside tempera-
ture indicator (P. 98)
*2Smart key system indi-
cator (P. 196)

1383-2. Opening, closing and locking the doors
◆Smart key system
Carry the electronic key to enable this function.
Grip the driver’s door handle
to unlock the door. Holding
the driver’s door handle for
approximately 2 seconds
unlocks all the doors. Grip
the front passenger’s door
handle to unlock all the
doors.
*
Make sure to touch the sensor on the back of the handle.
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4b004800030047005200520055005600030044005500480003[locked.
*: The door unlock settings can be changed. (P. 142)
Touch the lock sensor (the indentation on the side of the door
handle) to lock the doors.
Check that the door is securely locked.
◆Wireless remote control
Locks all the doors
Check that the door is securely
locked.
Unlocks all the doors
Pressing the button unlocks the
driver’s door. Pressing the but-
ton again within 3 seconds
unlocks the other doors.
Press and hold to open the win-
dows
*2 and moon roof.*1, 2
(P. 173, 178)
*1: If equipped
*2: This setting must be customized at your Toyota dealer.
Doors
Unlocking and locking the doors from the outside
1
2
1
2