My remote key fob for my 54 plate MJ had seen better days and it was difficult for my arthritic fingers to work the buttons so I bought a shell with blank key from ebay for £7. There were several slight differences inside. The battery contacts fouled the case and the transponder which was not a glass capsule and attached to the circuit board, hit the housing inside where a glass transponder would fit. Unfortunately I did not cut enough of the housing away and when I closed the case it pinched the transponder slightly. The circuit board mounted transponder is very fragile and it broke. Everything worked except the transponder. I took the car, the broken key and backup key into Bristol to Avon Lock And Key (01179 081144) to see if they could clone the good transponder. They cloned using a TPX4 which is about 20mm long. When I got home I decided to fit the long transponder across the fob at about the halfway point, it did not work. Undaunted I removed the remains of the original small transponder housing so that the new one lay inline with the fob with the tip right at the front. It worked! Supply and programming cost £40. I hope this story will warn anyone doing this to exercise great care, still it beats the Fiat price.
