Caddy dash probs

Having probs with my instrument cluster of my 02 plate caddy, which is just
a polo with a van bum. Anyway, when am driving the cluster will loose power,
all the dials will drop the clock will reset and so will the
milometer(sorry).  It only lasts for a second the goes back to working
normal. The total mileage stays the same though. The dash gives the
appearance of when you turn the key and start the engine even when the
engine is running. But now its starting to act up more. Sometimes when I
switch off ,the rev and speed counter twitch and a can see the oil light
flashing. But again, that goes away. Was having a look at the fuse box and
just started giving things a wee shake to see if it would make any
difference, and it did.

So, has anyone else had this kind of problem. Going to look at the thing in
the light of day and see what.  But does anyone know where in the fusebox
controls the inst cluster.

Am really sorry if this doesn't make sense but am really bad at putting
thoughts together. Would rather get it fixed myself instead of paying
someone to fix it, like it cost 40 quid to find out that a dodgy air sensor
had melted slightly and so smoking a lot when plugged in. A really hater
cars at times.

Cheers   Jim