The dash instrument panel on my 1998 Dodge Grand Caravan dies intermittently. No fuel, no odometer, no rpm's, no temperature reading. All gauges stay at zero. Also, the overhead gauge that allows me to check the temperature/direction/estimate is affected. I can get the temperature and direction from it but anything to do with the odometer or fuel gauges don't work (they remain blank).
The "Service Engine Light" turns on after each episode and the "ABS" light stays on for the duration of the problem.
It happened occasionally during the summer but now that we've hit fall, the gauges seem permanently off.
Also, the signal lights have stopped working. They stopped working altogether and then started again for half a day and are now not working again. Does not seem to be related to the instrument panel problem as it happened at different times but what do I know?

Optional Information:
Year: 1998
Make: Dodge
Make (other): Grand Caravan
Engine: V6?

Already Tried:
I have taken it to a mechanic who told me that my battery was running at less than 100%. He thought that maybe the battery didn't have enough juice to power the instrument panel. Switched out the battery and the problem went away for a little while. Seems to happen less in warm weather and more often in cold weather. The mechanic also said that it may be a corroded contact which would involve taking the whole dash off to fix - he did not check that out since it was a costly fix and the new battery seemed to resolve the situation (obviously it didn't since the problem came back). Any ideas?