Accenta 6 alarm system?

I have cut through a cable thinking it was a redundant telephone cable setting off an alarm in the speaker situated above the alarm box under the stairs. I have reconnected the 5/6 wires and 'reset' the alarm which stopped the noise but the alarm system no longer works. typing in the security number to 'set' the alarm simply sets off a pulsing sound from the control box with 3red zone leds showing.
power light is on with green on.. what do I do? I do not have a manual.