remote starter failing or just bad ground

code alarm ca-535 on 2000 Seville-came with car so dont know how old it is.  Siren intermittently making muffled sounds at inappropriate times, started once by itself and unlock/lock was intermittent.  Disconnected by pulling both 30 amp fuses but after discovering what could have been bad ground of siren and fixing it, everything appears to work fine.  Is there a good test I can perform so I feel confident it wont start by itself again?  Thinking I should just disable remote start and use keyless entry only but RS sure is nice.

How about ensuring all the grounds of the unit are properly in-tact! First thought whilst i was reading through the post was a ground issue!commit your way to jehovah and he will act in your behalf. psalms 37:5

Thanks for advice. If fixing siren ground "solves" the problem does that mean the ground under the dash from the main module is suspect or is the siren ground the only ground in the system?

I've seen installs where the siren was grounded in the engine bay and then ran through the firewall and connected to the ground of the unit I dunno if that's your case, but no the unit would also have a ground, the siren's gorund isn't the only grounding point!commit your way to jehovah and he will act in your behalf. psalms 37:5

2000 Seville now is not starting-security lockout even with good key  Was intermittent with ocassional blasting of horn when driver door was opened with key but would always start after it sat an hour or so except now.  Replaced Code alarm Ca-535 but no change. Trunk release on fob and dash switch also is intermittent and started about the same time.  How do I determine if I have a car issue (bad antitheft module etc) or it is related to remote starter wiring/457g bypass?  Will reprogramming the bypass do anything?  Need to know where to start to isolate the problem.  If I tow it to Caddy, they might not even know what to do because of aftermarket additions

First have the battery checked, voltage at rest, start up car then test, do a current draw test and do a load test, I suspect your car battery or a bad grounding issue.