Ordered a new flip key case,watched a few assembly videos. Had to destroy top half of original key to get the blade out. Threw it in the bin. Three days later car wouldn't start when I tried it for first time. Having re-shelled a key before for a different make of car I knew what it was. Thing is non of the YouTube videos mentioned the transponder so I assumed it must be built into the circuit board.

It is not but bonded into the top half of the key in its own compartment and they do not want you in there as it is glued. Crisis averted with a rake through the bins.

The transponder is not integrated on the circuit board.

The transponder is located inside the key part of the flip key. During production of the key the transponder is inserted into a pocket inside the plastic before both halves of the key part are glued together. To remove the transponder the plastic housing of the key part needs to be destroyed. 

New (aftermarket) flip key housings usually are unglued and without a transponder. In this case the transpopnder needs to be removed from the original flip key and put into the new housing. After the keyblade and transponder are installed the key part needs to be glued. 

15 hours ago, Trillionz said:

Crisis averted with a rake through the bins.

That will teach you what happens if you totally trust in anything you see on YouTube.

It is quite a bad crisis to lose the PATS transponder, especially if it is the only one you have!

I pulled the glued compartment apart with two pairs of pliers and then set about it with some side-cutters. I did try sanding it down with a sharpening stone but I thought any second I am going to take some of the chip away. The cutters luckily split it in the right place and it released the chip undamaged from its super glue. I put the new one back in with silicone so it will hold it but can easily be taken out in the future. I did not glue it back up and it is OK so far. Impressed at what I got for a little over £2.

Don't worry, I know someone who down the tip threw their whole bunch of keys in the crusher/compacter, never to see them again! No spares to had to be recovered to a main Stealer to be bent over for new everything haha

On the plus side the Torque app is telling me I have 7 error codes,some generated from the transponderless key!

So when my new Diagnostic tool the U480 turns up I will be able to test it. Got a code for reverse not working though which is a bit worrying on a "Powershift auto"