The speedo on my V70 suddenly stopped working with no warning at all.
The needle is just dead.  The odo works fine.  At the same time the
temp gauge became very erratic, mostly staying at the cold end but
occasionally moving to normal, but never above.  Even when it shows
cold the engine gives off heat via the heater.  Other gauges (fuel,
tach) work fine.

At the same time my Check Engine light started to flash.  By the way,
by ABS light turns on from time to time, but the ABS works fine when I
test the brakes.

Just previous to this my battery had died even though it is quite
new.  We had been doing a lot of short trips with seat heaters, fan on
etc. so this was not unexpected.  We have charged it and it is fine
now.

Can anyone explain all these problems?  Is my car haunted?  It is a 98
V70 with about 245K km on it.  It runs very well, shifts fine, etc.

The car seems to be quite driveable but I am wondering what might go
next.  Any suggestions as to what to check?  I don't want to invest a
lot of money in a garage replacing a whole lot of random stuff trying
to find the problem on this 10-year old car.

Thanks!