Maybe someone can shed some light…Dunno if it’s terminal or not

The other key works 100%
The central locking works
This key, the ‘spare’, will unlock the door/central locking by manually putting the key in the door.
It will start the engine.
The remote button will not unlock the doors
The light on the remote doesn’t light up
I’ve replaced the battery
One of the contacts on the battery cradle seems to be broken, so I’ve put some tin foil between the break hoping to bridge the circuit
Ive packed the key with some cardboard as per this video

Now I’m out of ideas, it’s the same key as in this video: https://www.youtube.com/watch?v=XfRdntC4eDE

Maybe I just live with the reduced functionality, just seems odd it will still start the car as I had the battery out for more than a few mins and the light doesn’t come on when pressing unlock…?

Tried reseting it? https://www.vauxhallownersnetwork.co.uk/threads/key-reset.61392/

Maybe I just live with the reduced functionality, just seems odd it will still start the car as I had the battery

They are two separate functions.

The RFID chip the immobiliser is looking for is passive doesn’t need battery.

This being the case I’ve moved the chip into a new key blank successfully in the past and had timpsons recut a key – you can often reprogram the unlock mechanism with the key in the ignition so long as you move the RFID chip over. You would need to find a working beeper mechanism -ebay perhaps.

I managed to get it working!
Seems without an additional reset it wouldn’t allow the remote to work.
The light still doesn’t work on the key when you press it which added to my confusion, but I don’t really care about that.

Cheers