Alarm Setting - Autotrail

if the large button activates and deactivates the general alarm, then its likely to be the smaller button that deactivates the internal sensors.

ours is similar bit has three buttons.....activate, deactivate, turn off sensors.

HiBoleroBoy

I thought that as well however small on its own it does not do it as when inside, after locking the doors & selecting the small button I can still open the doors without alarm.

I'm guessing but it possibly has to be both together or a sequence.

Ah, but can you open it from the outside without setting it off?

Good point - will try 

I had a Google earlier. Certainly,  one model of alarm from Brownhills requires the small button to be pressed within a  couple  of seconds of the larger arm button to disable the interior sensors.

I would think you need instructions as alarms are quite sophisticated and have other features such as ;

number of beeps / indication of alarm trigger & which circuit.

emergency PIN number to release the immobiliser 

emergency PIN number to release / switch off alarm.

Our Rapido has these functions , the key fob (2 button) locks the three doors and arms the locker and gas sensor circuits. A second press of the locking button deactivates the internal sensors as does a button the dashboard.

rgds