I have a '99 Voyager that is exhibiting some odd behavior.  While driving,
the instrument cluster will all of a sudden quit working.  No speedometer,
no tach, no engine temp, no fuel gauge, no digital readout for odometer or
for gearshift.  When this occurs, I also lose control of the rear wiper,
if it is on, it stays on, if it is off it won't turn on.  Also, when this
occurs, the transmission does not shift down to pass or climb a hill.  It
will accelerate from a stop fine and shift up to overdrive correctly.  The
ABS light (the ABS system does appear to work correctly when the condition
occurs) and sometimes the Check Engine light will also be on.

Turning the engine off and restarting does not clear the condition,
although it may go away during driving or after not being run for some
time (hours).

Can anyone give me a clue what to look for on this, it does not seem to be
related to any one system, but there must be some common link somewhere.

Thanks in advance