Issue with aftermarket keys

[RustRat]

When I bought my car, it came with two pairs (or bundles if you prefer) of keys. One bundle was with the factory one, which has a crack and may brake anytime, and an aftermarket one, without the "immobilizer chip" (I don't know ANYTHING about this, that's how the previous owner explained it, that's why I am asking). And the second bundle was an aftermarket key with an "immobilizer chip" which I lost, so ot doesn't concern me anymore.

In order to start the car with the first bunch of keys, I have to put the aftermarket key in the ignition, and have the factory key with the immobilizer thing make contact with it. Else, if I try to start the car without the factory key making contact, the car will fire up for a second, then immidiately stop running and a key light will flash on the gauge cluster.

My question, now. I ordered an Ultralite key. How can I make it work with my car, without having the factory key always with me? I also want to buy a Pole Position key, but I was concerned about this issue. Enlighten me, please!

[Phatmiata]

NA Miata with an immobilizer chip ??? :shock:

[RustRat]

Wait, what? They didn't come like this? Wtf is happening with my car?! I am not sure if it is somethimg installed by the previous owner, or I described something wrong. Fact is, if I try to start it with a plain aftermarket key, it won't start.

Should I upload a video tomorrow explaining what I mean?

[Martin]

I would guess the immobilizer is aftermarket and can be disabled or removed

[RustRat]

That's something I didn't know. Thanks guys. I will find a way to disable it.

[RustRat]

As reverant (the dude that makes the Megasquirts) told me in a local forum, '96+ models had from the factory (at least the 1.6L models in Europe). The more you know...

[Malibu Q]

Is the factory key able to be disassembled?

One of my Mx-5's has an immobilizer key which can be pulled apart and the key blade can be replaced. My local key shop was able to cut and reshape an aftermarket key to suit.

If the alarm has a proximity sensor as a switch, maybe you could remove the column shroud and find the sensor. Then just tape the old key to it inside the shroud as a temporary fix.

Not seen a key light in the cluster before though

[RustRat]

https://www.dropbox.com/s/v23mnc4j2yg2q8r/20150327_081027.mp4?dl=0

Direct link to the video in my dropbox folder.

First you can see i start the car with the aftermarket key w/o imobilizer, and the key light flashes. Then I start it with the original key w/ imobilizer very close, and everything is ok.

That's an interesting "hack" you are suggesting, Malibu. I'll consider doing that, thanks.

[Martin]

As reverant (the dude that makes the Megasquirts) told me in a local forum, '96+ models had from the factory (at least the 1.6L models in Europe). The more you know...

I did not know that. Interesting :)

[Malibu Q]

Watched the movie.
There's almost certainly a proximity switch inside the column shroud.
Seems strange that there's a circuit inside a sealed key without any power supply (magnet?)
If you can find the switch inside the column, maybe you could easily replace it with another 'hidden' switch.
May have a few wires coming out of it though.
Maybe: power, earth, input, output

[RustRat]

I found out something new, in case anyone is interested. Indeed there is a proximity switch, and it's the ignition ring that triggers it.

I must admit it doesn't look very OEM-like but who knows,

I'm thinking to extend the wiring and hide it behind the glovebox, or create something more fancy, like a second keyhole hidden in ghe center console, maybe add a switch for added security. Dunno. Any thoughts?

13925

[MemphisMiata]

In the early days of Immobilizer keys here in the US when you wanted to do an aftermarket Remote Start, a "redneck" solution was to take the steering column shroud apart & tape a key on top of the ignition switch, or cut out the immobilizer chip & super glue it to the top of the ignition switch.
This essentially disabled the immobilizer...but didn't help much when it came to preventing theft!

Nowadays, the aftermarket remote start industry sells "bypass modules" that "talk" to the remote start unit.
When you press the remote start button on the key fob, it sends a signal to the bypass module, which temporarily removes the immobilizer from the circuit, allowing the aftermarket remote start to crank the car.
This bypasses the immobilizer if you have the key fob, but leaves it in the circuit if anyone tries to hotwire the car.

I have never seen an aftermarket immobilizer...but there's a first time for everything!

[Malibu Q]

That's definitely the proximity switch. I was talking to the mechanic at work about it today. He has seen it in Mazda built Fords. He described a coil wrapping around the ignition barrel and energising the key. Evidently you should be able to see where they drilled the key and inserted a small pellet shape chip.
You can't bypass the switch as it sends a coded message to the CPU. The key, switch and CPU are a matching set.
The Temic immobilizers are built into the ecu and are very difficult to remove. To remove it the ecu requires a new board fitted to emulate the immobilizer. Croatian company Autodijagnostika can do it.