Rev counter bust on Citroen Xara AX 1.6

Some of you may recall my friend's Xantia that threw its cambelt the other week. She's now replaced it with an S-reg Xara AX 1600 petrol manual.

The rev counter doesn't work at all, which is no great issue, but I thought if it is easy to fix then I could earn some brownie points.

Is the rev counter cable driven or electronic ?

Is it a known problem ?

Obviously the fix will depend upon what's wrong, but from your experience can you suggest whether it is likely to be a pig to fix or pretty straight forward.

I don't want to spend ages fixing it, 'cos it's no real loss without it, but if it's gonna be a quickie then I'll do it.

Also, on a general note, does this car have any typical known problems ?

Thanks in advance.

Jeff :0)