Car Alarms: Viper alarm not working, except when car started, alarmtek, optonline net

Question
I bought a 97 eclipse about 2 years ago that had the Viper 500HF installed on it.  At first everything was going ok, until all of a sudden the alarm stopped working.  As in I couldn't lock and unlock with the remote, so I just started using my key to lock and unlock the car.  I notice that when I start the car, the alarm will go off (faint but can hear it if your close) and the red light in the car will flash for about 5 minutes (I am guessing because I hear it when I stop the car in short trips, but I don't here the alarm after a long trip)  Any idea what could cause it to just stop all of a sudden and how to fix it?  Battery is fairly new and working great.

Answer
Your question prompted this
automated responce to a
DEI equipment support inquiry...

DEI EQUIPMENT SUPPORT sERVICES ARE NOT
PART OF THE INFORMATION THAT I OFFER HERE
AT ALARMTEK.

You must have missed that big note I placed
on the ALLXPERTS site. It was pretty clear.

You have the wrong guy here. I don't
provide support for DEI equipment or they're
clientel, PAST or PRESENT.

Too many people have been asking
for the service they should be providing, and
I won't do they're job here any longer.

I now refer these inquiries to either my forum
at www.installsupport.com, www.directed.com
or, I even have a couple of guys at
sales@tampacaralarms.com or,
ctursi@optonline.net , who might be able
to offer some insight.

Both good guys and they will treat
you right.

Good luck with your
DEI info quest.

ROBERT MARTIN/Owner
ALARMTEK AUTO ALARM