Car key question

[Lannister902]

Hi,
My key fob casing broke on my Honda Jazz. I got a replacement on ebay for a few quid, thinking I could just swap everything over.
Now the fob opens/closes the doors, but won't start the car?

After further inspection, it looks like this little thing on the old/broken fob is missing on the new fob. I'll already make the presumptions that's the problem...



What is it?

[paintman]

Almost certainly the security chip - looks very similar to the one in Mrs p's Peugeot.
You need to transfer it to the new fob as without it it won't start.

[Pilotguy]

The immobiliser system transponder. “Talks” to the car’s immobiliser circuit so that only the correct key starts the car. Have you kept the old key? You should be able to swap the transponder out of it into the new fob.

[Scrump]

As others have said it is a transponder pill for the immobiliser. You need to swap it over from the old key.

[Penelope Stopit]

As all above

Transponder needs sorting

[Lannister902]

Thank you