Veritas 8 alarm, cut through sensor (pir) wire - help?

Hi
I was recently doing some DIY and removed a skirting board. Unbeknown to me inside it was the wire that leads to the sensors for my alarm. I imediately went to B&Q and bought a junction box the type that u match the colours either side shove the wires in and they cut thru the plastic to make a contact. Switched it all back on and the 2 zones 2 and 3 (the cut ones) remain lit on the control panel and there is beeps. The sensors are not flashing red either. So I undid the junction box and exposed the metal in the wires and twisted each of them to the corresponding colours, the alarm sounded outside.. i put my code in, it went off but zone 2 and 3 remain lit. Im unable to put my alarm on now. Im wondering after the wires are connected back up if there is a hidden button on the sensor i need to press or do i need to re programme the sensors back to the control panel? please any help appreciated as i dont have the money for an engineer! thanks very much