Veritas R8 PIR problem

["diy-newby" <asas@xxxxxxxx>]

 Hi guys

We have a Veritas R8 alarm system. This morning we noticed that walking into
the kitchen did not activate the part alarm unset procedure. I performed a
walk test and both the kitchen and the living room PIR are not working.

The red light in the PIR still works, it is just not activating the walk
test procedure. Are PIR's self powered with an internal battery or do they
take power from the main alarm panel? The reason I ask is I have put quite a
few chipboard screws in the upstairs chipboard floor to cure loose /
squeaking boards, and am now thinking worst case scenario that some how a
screw has pierced a cable. But if the PIR takes power from the panel this
hopefully cannot be the case as the red light in the PIR still comes on upon
detection.

Can PIR's fail but the red light still activate?
Could this be a problem with the main alarm panel? Is there any other tests
which I could carry out to narrow down the problem?

TIA