On Thu, 30 Jul 2015 14:44:01 +0100, Dave Plowman (News) wrote:

The panel on the alarm itself still works normally. They are both the
early type of touch screen, not proper push buttons

What do you mean by "touch screen". Rubber bobbly buttons like a TV
remote that do depress. Smooth plastic, with printed numbers, slight
indentation for the active area, essentially no movement but still
requiring a definate push to enter a number. Or touch screen as in
mobile phone?

I'd carefully remove it from the wall and check for a loose/corroded
connection into the cable back to the panel. If it's the flat
membrane type, it might be a sealed unit or might just be a flexi
folded onto itself. The latter will be cleanable but be careful of
any tracks that cross the fold and that might be where the fault is.
If everything looks OK, try it on a short bit of cable direct into
the panel, maybe you have had a little grey or brown furry visitor...

--
Cheers
Dave.