Please Help!

My 98 Dodge Grand Caravan has approximately 98,000 miles - when I got the van, the gauges would work (intermittently) and the ABS light would be on. If I would bang on the dash they would start to work again but shortly go out until the banging would kick them back on. They are completely gone now and both the ABS light and the CHECK ENGINE SOON light are on. My dash lights and clock light are very dim and flicker now as well as my windshield wipers only work on "fast" and "super speed" settings and if I turn them off, they stop in their tracks. I checked all the fuses and they are good still - I have a mechanic willing to check the wiring behind in the instrument cluster and see if cold soldering would work but if it doesn't I am still out the money for him to try - SOMEONE PLEASE HELP ME!