I managed to sort it out.
I fitted the ignition switch barrel assembly from the spare donor 306 I have.
I removed the circuit board and little black transponder chip from my existing key, and fitted those into the key that fits the donor barrel.
A very small plastic lug had broken on the plastic electrical switch housing on the barrel assembly. I think the broken plastic lug was fouling the electrical switch mechanism and preventing it from turning properly. I removed the broken lug and the faulty barrel appears to work well again. I can't fathom out what the plastic lug does. It seems to cushion or locate the steering lock bar or something.
I will keep the old barrel as a spare!
Thanks for looking.
I fitted the ignition switch barrel assembly from the spare donor 306 I have.
I removed the circuit board and little black transponder chip from my existing key, and fitted those into the key that fits the donor barrel.
A very small plastic lug had broken on the plastic electrical switch housing on the barrel assembly. I think the broken plastic lug was fouling the electrical switch mechanism and preventing it from turning properly. I removed the broken lug and the faulty barrel appears to work well again. I can't fathom out what the plastic lug does. It seems to cushion or locate the steering lock bar or something.
I will keep the old barrel as a spare!
Thanks for looking.