Perhaps others have asked the same question in the past. However,I hope
someone can still reply me with this question.
The car key comes in a set of two identical keys, and a "master" key.
The two keys has the lock/unlock button, and inside it has a battery.
The master key is solid block... appears not to have any battery.
My question is this. Has this key an immobilizer? What is the prime
component of an immobilizer?  The dealer told me once that with the
key, it can identify whether you are entering the right key in the
keyhole to start the car engine.
How does the immobilizer work with the "master" key?  Does it have a
"chip" inside the key... where?  What energy it uses up, if there is no
battery?
Also... with the twin keys that has the battery.... Do each of them has
a embedded chip too?
Or is the only protection on the key is the different style grooving of
the key ONLY..... which you cannot duplicate in a regular Walmart
store.

If your twin keys start to break down (wear and tear)... or if you
share the car with three peoples, is it wise to use the "master" key?
Should master key only be used in emergency only? Why do you need a
"master" key?  Would the dealer be able to duplicate key if you just
tell them the number/code from the little steel stub/tag that comes as
a separate little piece with your car keys?  Do they actually need the
key to make a duplicate?

Since I am asking question.. perhaps anyone can also answer this. The
garage opener inside the car is synchronized with your garage door. Is
there a battery in the unit, or does it use the battery from the car.
Same question with the tiny light for the rear mirror for auto dimming.
Is the source energy from the car battery or an extra external battery,
like the car keys?

Thanks for info.