OMG my friend you have a Gremlin! They are not fun, as they hide in tough spots. First thing is to check the voltage of the battery and hope that its low. If it IS a good battery, it is time to start wire hunting. Especially seeing that its vibration triggered. If beating the chit out of your dash is getting results, I'd start there. Remove the dash bezel, radio, gauge cluster and start looking for wire harnesses close to metal components. If you can, move the harnesses away from the metal, if they seem like theyre gonna work their way back to the metal...put some electrical tape on the metal where they would touch. These issues are not fun and I wish you the best, and hope that anyone that has had the same issue chimes in.
