Cadillac Repair: 99 deville - alarm problem due to no stock radio, stock radio, aftermarket radio

Question
I have a problem with my alarm/keyless entry not working after the car sits for a while. When i start the car the alarm will go off. I can turn the key to ON and the alarm will go off, and then i can hit the unlock button and it cooperates after this. This is very random. I’ve owned the car for 4 months now and this has happened ever since I got it. It’s been in the shop twice for this to no avail. I was talking to a local radio shop and they mentioned that they had this happen on a similar Cadillac after removing the stock radio (mine did not come with the stock radio when i bought it). They said they finally resolved the problem by putting the stock radio back in the trunk using a special harness to make the distance. I have also seen other references to this problem on the internet and I’m sure my issue is due to the stock radio being gone. Since I never had this radio, how can i fix this problem? It’s driving me nuts.

Answer
The radio is part of the anti-theft system and you will have problems with the anti-theft until you replace the radio with factory radio and have it reprogrammed into the anti-theft system by the dealer.

Now there is a possibility that a radio repair center may have a way to integrate an aftermarket radio to comply with the anti-theft system but you would have to check with them.

I have seen this same problem numerous times.