1996 Volvo S40 - Electrical Fault?

Posted on behalf of a friend......... Can you help ??

<snip>
Took the wife out for a driving lesson at the weekend, and
after a few stalls at junctions decided to try her on a quiter road. On
getting back into the drivers seat I noticed that a door indicator light was
still lit (general light on dash). I got out and re-checked all of the doors
+ boot (opened/closed) but all were closed tight. Reluctantly I got back
into the car a pulled away. I then also noticed that the digital readouts
and analogue dash displays were not registering speed, fuel, revs,
etc...though the engine, indicator, door open, etc lights were all working
as expected. Upon getting home and checking the systems a little further I
also discovered that the radio, internal lights, and central locker were
also not working.

Now, I have checked ALL fuses, both under the dash and in the engine
compartment but were okay. As none of these failed systems are supposed to
have a common connection through the fuse box I was wondering where the
problem may lie.

One word of note is that we have had a faulty passenger side sun visor for
some time that continually needed forcing into postion. This had a mirror
with light. I thought that this may have caused a short somewhere so removed
it last night and isolated the two wires with tape. This unfortunately did
not make a difference.


Any Suggestions.....?????

</snip>

Cheers
Adrian