Pontiac Repair: 94 Transport HVAC issues, blower motor resistor, gauge panel

Question
My Transport recently lost my heat, I first thought the blower motor went out, got a lifetime warranty replacement.  Not the answer, fuse was blown, replaced it took a corner and it blow again.  Changed blower motor resistor and still not the complete solution.  I probably needed to change neither...but on to my point.  Heat works, but my gauge panel goes crazy when I hit bumps...so it must be a ground.  I just cannot find it hope you can tell me where the ground is at.  I also think my switch is going bad because I lost 1st speed.  Could it be a fluke problem with the switch arcing?  When I shut the heat completely off, then I do not have a problem with my gauges surging so I really believe that it is a bad ground...just need to find it.  Sorry for rambling for so long...but I believe that the whole story helps.  Thanks

Answer
Hi Brian:
I think your right dead on. That it is a ground issue or one giant draw/short. I don't have access to the older cars service manuals back past '98 So I can't help you with what ground is the issue either. There are a couple of them on either side of the dash board and one on the bracket for the steering column. Check the ones on the body/ fram from the battery make sure they are clean and tight. Also under the hood look around at the harness that goes to the blower motor.the resistor and the hi speed blower relay. If you have a really big draw that will cause #1 the fuse to blow and #2 for it to draw down the battery voltage for other devices before that fues were to blow again. I doubt that the switch would be arching the switch doesn't really have a very high current draw the big draw is when the fan is on high and that is why they use a relay for Hi speed because of the high current draw. No you were not rambeling You would be amazed at the questions I'm asked with little to no information at all. Good luck and Happy holidays :}