What's type of immobiliser?

[noxati11]

Hi, does anyone know what this type of immobilizer? It replaces the keyboard on my type. I have long wanted to ask someone about it. I've never seen Xantia with similar immobiliser :/. It's definitely aftermarket. I got my Xantia from my grandfather and he already doesn't know where it come from.

[Zelandeth]

Think I've seen that on various 90s cars that came in through the garage badged as various different brands, so probably some nameless Chinese OEM that makes them. Seem to recall them being particularly common on Vauxhall Fronteras.

We usually removed aftermarket alarms/immobilisers unless they were obviously professionally installed as they had an annoying habit of causing problems under warranty.

One of the very few times I got stranded was when a (not cheap!) Cobra branded unit went haywire in one of my Saabs. Remember spending a good couple of hours standing on my head in the footwells bypassing the blasted thing in a dodgy part of town.

[spider]

Can't see how that would bypass the keypad unless its just been unplugged or the CPH/Texton is unplugged and that is used instead.

They can go wrong (those touch key units) as said.

They are also a pig sometimes to remove as the 'box' itself is sealed tight and welded shut and all the wiring is black too. Typically it has two relays inside (so that's four wires) and then three more (perm 12v/ earth / ign 12v) , all these are black and the same thickness to confuse. As well as that there's a couple of thin wires that simply link the 'touch keyhole' (the bit on the dash) to the 'main box' ie the metal sealed unit.

I did dismantle one once and found the pcb inside to be sealed inside some curious hard resin that shattered the board when I tried a 'brute force' method of investigation , a mixture of horror and facilitation to be honest.

[noxati11]

Thanks for reply. So if the key goes wrong, only chance is get bypassed ECU somewhere?

[dnsey]

Even if all the wires are black, it should be possible to identify them using care and logic.
You can then bypass the immobiliser altogether (of fit a hidden switch etc, if you prefer).
I designed a similar system for my BX many years ago, using a magnetic reed switch hidden in a random location behind the dash to unlock it.

[spider]

You don't need a bypassed ECU as that is already done by what was installed. Either the Texton/CPH is disconnected or the keypad is, rendering the factory immob dead (well, kind of dead)

Agree a bit of time and care will find out what was done. Typically the two circuits are an ignition feed and starter feed or two ignition type feeds, ie fuel pump and ignition or ECU ignition feed.

[Stickyfinger]

does this help
http://www.ebay.co.uk/itm/NEW-COBRA-CAR ... 0806948710" onclick="window.open(this.href);return false;

[noxati11]

Thanks !