JohnnyCake

When installing the LuxLink remote start (and I assume any remote start), the flat key has to be secured inside the car. Why?

I was thinking that it was so that the imoblizer was disarmed. But then I noticed that my eBay key with no electronics (which I hid outside the car for when my wife locks the real keys in the trunk) will crank the car, but the car won't start.

How is it that my no-electronics key cranks the car, but it won't start it, whereas I can remote start the car with no key at all?

Habious

The LuxLink Remote start works like the kids in the movies when they "hotwire" a car. It takes the two wires that go to the starter and shorts them together, making the starter go. However, the Imobilizer won't let the fuel pump run unless it senses the chip inside the key. No fuel, no start.

The LuxLink kit is actually pretty neat in that it only activates the Imobilizer deactivation circuitry when it needs to start/run the car. So, you haven't lost that security feature.

Does this help or just confuse things further?

JohnnyCake

I think I get part of it:

LuxLink: hotwire car, deactivate imobilizer circuity = start
My "dumb" key: crank car, but imobilizer still active = no start

What role does the flat key play in the LuxLink install?

Habious

The flat key holder contains the same kind of chip as the "real" keys. It's not in the flat key itself, it's in the flat holder that goes into your wallet.

Where you bought a "dumb" key for your wife to open the doors - but it won't start the car, I bought the "smart" electronics - but didn't have the key cut - to use in my Imobilizer deactivator. So, even if you broke into the LuxLink module, you couldn't use it start the car (they key isn't cut so it won't turn the ignition).

To actually start the car, you need both pieces of the puzzle - you need to dactivate the Imobilizer (with one of the chips) AND you need to be able to crank the ignition. We're both using only 2 half of that equation, for different purposes but, for the same reason (security).

KiPod

iTrader: (31)

I have a remote start in my 2GS. It has a seperate box under the dash, away from the ignition cylider, where you place the spare key inside a ring in the box. There is a cable that connects to another ring you put around the key cylinder. When the remote start gets the signal it uses the two rings as a antenna to boost the keys range up to the cylinder. I tried to start my car with a hollow key to test if the car would pick up the hidden keys signal at all times but the car would not start. In my case the remote start has to be active to "broadcast" the spare keys signal up to the cylinder for the car to start. If that makes any sense.

JohnnyCake

That's the part I don't get. So if the flat key chip is permanently in the car with the LuxLink install (one piece of the puzzle) and my dumb cut key can crank the car (the other piece of the puzzle), what keeps it from starting?

I'm glad it doesn't for security purposes, but I am curious as to the theory.

KiPod

iTrader: (31)

If the Luxlink is the same as my remote start it will not send the signal unless the Luxlink is active. The LuxLink being active is the 3rd missing piece of the puzzle.

Habious

Exactly. The LuxLink "triggers" the Imobilizer deactivator ONLY when it needs to. If it was always broadcasting, the "Security" light would never blink anymore.

When the "Security" light is blinking, that means that the Imobilzer is active and the car won't start (because there's no fuel flowing to the engine). If you notice when you put a real key into the ignition, the car detects the presence of a valid "chip", the light stops blinking, and the car will start.

When the LuxLink unit tries to start the car (and ONLY when it's trying to start the car), it sends the signal down the wire to the antenna that's wrapped around the ignition cylinder. In a sense, it's telling the car (using my best New York accent) "I got your key right here!".

If you wanted to, you could simply tape a spare key up inside the dash around the ignition cylinder; then the car would start no problem. However, this would basically permanently disable the Imobilizer, this defeating one of the security features of the car. Obviously, the LuxLink solution is much more elegant.

KiPod

iTrader: (31)

Now thats MD, DC, & VA working together.

JohnnyCake

OK, we have hit a bullseye what I don't understand. The security chip is passive. Like you say, you could tape a spare key up inside the dash. Isn't that exactly what is going on with the flat key? So why isn't the flat key telling the car "I got your key right here" all the time (or at least when I stick the "dumb" cut key in the ignition)? Is there some difference btwn the flat key and the real key (besides its flat)?

Habious

The flat key doesn't contain the security chip, the plastic cases that houses the flat key does. See the picture below.

JohnnyCake

Well, I meant the case. It's in the car all the time with the LuxLink ("close to the ignition switch"), so why isn't it telling the car "OK to start" when I put in my dumb key and crank?

Habious

The chip has to be RIGHT up against the ignition cylinder for it to sense it. The Imobilizer disabler takes the signal, amplifies it, and sends it (via a wire) over to the ignition. During the installation, you wrap a loop of wire around the ignition cylinder. This is the antenna. Basically, when the LuxLink unit is ready to start the car, it powers up the Imobilzer disabler which takes the signal from the chip, amplifies it, and sends it down this wire to be rebroadcast through this antenna loop for the car to receive it.

The chip doesn't have a battery...it's essentially what's called an RFID tag (Radio Frequency Identification Tag).

This is from Wikipedia on RFID tags....

Passive RFID tags have no internal power supply. The minute electrical current induced in the antenna by the incoming radio frequency signal provides just enough power for the CMOS integrated circuit in the tag to power up and transmit a response. Most passive tags signal by backscattering the carrier wave from the reader. This means that the antenna has to be designed both to collect power from the incoming signal and also to transmit the outbound backscatter signal. The response of a passive RFID tag is not necessarily just an ID number; the tag chip can contain non-volatile, possibly writable EEPROM for storing data.

So, the LuxLink Imobilizer disabler acts as a booster for this signal. If the key were placed too close to the ignition cylinder you wouldn't need the amplifier and, as I stated before, your Imobilizer would ALWAYS be disabled.

By placing it a little away from the ignition cylinder, the Imobilzer only gets disabled when the LuxLink wants it to.

Am I helping here or just making it worse?