Car Alarms: Alarm arms but wont lock doors, ungo alarm, gmc sierra

Question
I have a 2006 Gmc Sierra with and aftermarket Clarion UNGO alarm on it and just recently I've had issues with it not locking with the remote. It will arm the alarm but will not lock the doors and I have to use the buttons inside to lock it then arm the alarm. What would cause this and how can I fix it?

Answer
Complex locking system. I would look at the combination
door lock/Passkey bypass kit that the installer used.

This is usually where the problems of control would be,
in the transmitter.

Have it inspected by the installer to see if there
is a conflict or fault.

Good luck.

ALARMTEK.