2021 TOYOTA SIENNA HYBRID ECU

7Introduction
INTRODUCTION
THE IMMOBILIZER KEY

THE NEW WORLD OF
ANTI-THEFT TECHNOLOGY
This Toyota vehicle may be equipped
with an electronic “immobilizer” anti-theft
system. When the key is inserted into the
ignition switch, it transmits an electronic
code to an immobilizer computer. The
engine will only start if the code in the
key matches the code in the immobilizer.
If the code does not match, the immobilizer
disables the ignition and fuel systems.
While an exact physical copy of the key
will open the door and allow retrieval of
items locked in the vehicle, it won’t start
the vehicle unless the key has the same
code as the immobilizer.


SECURITY
For security purposes, access to key
codes and service procedures for
electronically registering replacement
keys is restricted. Only a Toyota dealer
or certain bonded/registered independent
locksmiths can generate replacement keys.
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8Introduction
INTRODUCTION


REPLACING THE KEY
Upon purchase, each vehicle should have
two master keys and an aluminum tag
with a key code imprinted on it.
To generate a fully functional replacement
key (one that will both open the doors and
start the engine), one of the master keys
is required. To make a key that will open
the door for retrieval of items locked
inside the vehicle, the aluminum key-code
tag can be used. If a master key or the
aluminum key-code tag is not available,
a Toyota dealer or certain registered
locksmiths can obtain the key code from
a restricted-access database. These
businesses can also access a service
utility to reprogram the immobilizer if
all registered master keys have been
lost. If a Toyota dealer is not available,
please refer to www.aloa.org to find
a bonded/registered locksmith who
performs high-security key service.


KEEPING THE KEY SAFE
Replacing an immobilizer key may be
costly. It is advisable to keep a spare
master key and the aluminum key-code
tag in a safe place. If you record the
key code in more than one place, do not
record it in a way that can be easily
identified and associated with the vehicle.
It is wise to keep a copy of the key code
outside of the vehicle.
If the vehicle was delivered with less than
two keys and the aluminum key-code tag,
consider having the Toyota dealer or a
qualified independent automotive locksmith
make a duplicate key before you need it.
THE IMMOBILIZER KEY
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55Maintenance Log
MAINTENANCE
Driver’s Floor Mat
• Only use the driver’s floor mat
designed specifically for the model
and model year of your vehicle.
• Always properly secure the driver’s
floor mat using the retaining hooks.
• Never install another floor mat on top
of the existing driver’s floor mat.
• Never install the driver’s floor mat
upside down.
Engine Air Filter
Inspect or replace at specified intervals.
When performing inspections, check for
damage, excessive wear and oiliness,
and replace if necessary.
Engine/Inverter Coolant
Drain the cooling system and refill with an
ethylene-glycol type coolant. Inspect hoses
and connections for corrosion and leaks.
Tighten connections and replace parts
when necessary. A qualified technician
should perform these operations.
(For further details, refer to “Radiator,
Condenser and Hoses” in the “Maintenance
and Care” section of the Owner’s Manual).
Your Toyota is equipped with Genuine
Toyota Super Long-Life Coolant. The
replacement intervals for engine coolant
recommended in this booklet are based
on replacement with Genuine Toyota
Super Long-Life Coolant or similar
high-quality non-silicate, non-amine,
non-borate ethylene-glycol coolant with
long-life hybrid organic acid technology
(i.e., a combination of low phosphates
and organic acids). If another type
of ethylene-glycol coolant is used,
replacement intervals may be different.
EXPLANATION OF MAINTENANCE ITEMS
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