viper 350 plus zone 4 problem

I install a viper 350 plus with glass sensor on a 2001 Lincoln Naigator. The customer keeps complaining that the alarm keeps going off every 20 to 30 mins some days and some days not, The alarm is giving 4 chirps when he disarms and the led flashes 4 times, this is a zone 4 on this alarm which is aux sensor, turned down the sensor, he said that it worked for that night, but started going off again, so I unpluged the glass senor all together thinking that maybe it was bad, Still triggering and still a zone 4 ???  customer is getting all kinda complaints from neighbors and from his apt. complex manager.  Any suggestions

Have you toned down the shock sensor?commit your way to jehovah and he will act in your behalf. psalms 37:5

I have, and the shock sensor is Zone 2....

Defective unit!commit your way to jehovah and he will act in your behalf. psalms 37:5

Does this vehicle have a Passive Anti-Theft System..?common on Lincoln Navigators. A bypass unit is used for this instance. It may be interfering with the 350. Are there any loose connections? Is there any kind of wake up module that could be triggering the door circuits? Otherwise, I would assume it is a defective brain. Maybe swap it out and see if there is a change. Personally I would scrap the 506t and go with a Prox sensor. Much more reliable.

Bypass? It's a basic entry system no remote start!commit your way to jehovah and he will act in your behalf. psalms 37:5

Ok. Wasn't sure if it had a factory anti theft system installed.