Older Viper alarm

[sirpat]

I have a 1983 380SL with a Viper alarm. The remote has two buttons but only one seems to operate the system. When I activate the system the doors and trunk lock and the alarm arms and I get one chirp type sound and when unlocking I would get multiple chirps. Recently the doors & trunk continue to work but I get no chirp sounds and the alarm does not activate, any ideas would be appreciated. Also I would like to know where the components are located so I can check connections ect.
Thanks Harry Crim Tucson Az.