Xantia replacement key

[evilclive]

2001/W Xantia (ie mk2).

I wanted to get a new ignition key, so went over to the dealers who ordered one. The immobiliser then needs telling that the key is good, but apparently the car has had an ECU change in the past, and all paperwork related to this has vanished, so the dealers were unable to complete the job.

I've now got another dumb key which won't start the car. Is there any way out of this, short of replacing the ECU again (not an option...)?

[meexi]

if you open the key you will find a little rectangled bit of metal swap them over into your new key and then it should work

[evilclive]

Unfortunately I want a spare key, so that's not going to help

[meexi]

tape the bit of metal next to your ignition switch

[evilclive]

I have actually considered that. Are there any downsides to that apart from the obvious security problem? Eg does the car say "your key's still there" when you switch the engine off and open the door?

[meexi]

never thought about that

[DickieG]

How easy is it to prise out the transponder from the key without damaging it,,,,,,,,

[wheeler]

2001/W Xantia (ie mk2).

I wanted to get a new ignition key, so went over to the dealers who ordered one. The immobiliser then needs telling that the key is good, but apparently the car has had an ECU change in the past, and all paperwork related to this has vanished, so the dealers were unable to complete the job.

If the ECU was replaced it should have been coded with the same access code as whats originally in the CPH otherwise the car wouldn't start ?
The only way the code can be changed is if the ECU and CPH were changed at the same time, you would then use Lexia to tell it the new code & both units must have the same code. I cant understand why anyone would have changed the code ?
Another solution is to take the key along with a working key to an auto locksmith, some types of transponders can be 'cloned'. I believe some branches of timpsons have this kit.

[evilclive]

In case anybody is interested, I had another go with the key blank from the garage and the key code they had with my lexia. First attempt failed again, but I then asked somebody if the code the garage had given me was correct and it transpired it wasn't - or at least my reading of the code wasn't. Tried the right one, now I have a working spare key I suspect the garage made the same mistake I did.