My son has bought himself another GTV today. The remote alarm fob is a sigma, which to my knowledge is an after market alarm system. Is it possible the Alfa system has been replaced/overriden or that the sigma remote just a replacement for the original, how could we find out? Sorry if this is boring old ground for the old hands on here, I did search the threads first but that in itself is a massive task on this topic.
You didn't say what phase/engine size he bought but I think some Gtvs were fitted with Sigma alarms. Have a look at the alarm unit on top of the front offside wheel under the cover, you should be able to tell if the wiring is original or aftermarket.
Its a phase 2 3.0 litre. I've now found a receipt for the fitting of the system when the car was 4 years old. I thought that if it has replaced the original it might be useful to other owners with key and alarm issues. I obviously need to have a good look at the car. Thanks