how to remove pir cover?

we have accenta g3 model but the tamper lights keeps flahing tamper light we thinks when christmas went up they knocked the alarm box outside we check it and its on ok check pirs they are fine been told we have to put in engineer code but dont know it (company gone out of business) nothing on instruction paper work can you please help me
07956 228972
kind regards
bob

bob
December 2009

i dont think thats an option take it off if it sets the alarm off then just enter your code press reset then when you have finished put them back on proper and you should be fine ; death

death
December 2009