Okay. Use the steps below to reset the system. If the problem continues then you may have a problem with the door lock sensor or with the body control module. I would recommend getting a transmitter for it.

1. Place the shift lever in P (PARK).
2. Turn OFF the ignition.
3. Open any door.
4. Lock the doors with the LOCK button on the transmitter or power door lock switch. The system is in open mode and will not start the arming timer until all doors are closed. The security indicator will flash quickly. IMPORTANT: The system is not armed if the doors are locked manually. The remote keyless entry transmitter or power door lock switch must be used to arm the CTD System.
5. The system will arm approximately 30 seconds from the time that the last door is closed. During this delay the THEFT SYSTEM indicator will be flashing quickly. When the indicator transitions to FLASHING slowly, the system is armed. Passive CTD Arming Through vehicle personalization, the CTD system can be set to arm passively with no input from the vehicle operator. Passive CTD arming will not lock the vehicle doors however. Use the following procedure in order to passively arm the system: