problems with viper 791xv remote start

I installed  a Viper 791xv on my 2002 GMC Sierra in 2005. I also installed the shock sensor, radar essentials 508D radar field disturbance sensor (proximity sensor), backup battery, the GM Passlock. When I remote start it, it tries to start but dies immediately. It doesn't do it everytime, but if I wait for 10 minutes it will start with the key. one time it wouldn't start at all. My brother worked for Chevy dealership and asked a guy to look at it for me, he said it was the Ignition Cylinder Housing and the passlock sensor in it was bad. I changed it and they had to program it. Well it didn't do it for about a yr then did it out of the blue. I never know when it's going to happen. Any advice would be appreciated.

Is this an old install or is the Viper 791xv recently installed? Sounds like passlock issues, yet again.

get rid of that bypass module

do this instead:  

http://documents.codesystems.com/700055.pdf

Sorry it took so long to reply catback. I installed the Viper 791xv in August 2005. A local car audio shop gave me the wire diagram for my truck. everything works fine except the problem with the remote start.