Needles on all the guages are jumping when car is

take the cluster out of dash-pull the plugs apart and re-plug a couple times,also do this with the main cpu-the connections can also corrode-and could be cleaned up-a tool to do this can be bought at an auto parts store-looks like a bunch of skinny files-
cheers Denny

sounds like you are losing ground,make sure your battery terminals are clean and tight

did you check out the battery cables,some times they can get corrosion inside where it cant be seen and cause a short, and lack of output and sonetimes will mess with the charging system.it happend on my 87.

IF WHEN YOU TURN YOUR KEY TO START YOUR DASH LIGHTS DIM AND HEAR A CLICKIN NOISE YOUR BATTERY IS LOW,IF NOT THOUGH AND THEY STAY BRIGHT AND NO CRANKING THE STARTER SOLENOID IS MALFUNCTIONING OR ITS ELECTRIC CONTACT IS CORRODED OR YOUR KEY SWITCH IS BAD.

Check all fuses under hood and on end of dash don't just look test them, 95 dodges had a recall on key switch burning out, bad connector in column and to relay under dash, check all those options

check your grounds

Disconnect the crankshaft position sensor and turn the key on. See if the "no bus" message goes away and the gauges come back to life. If so, replace the crankshaft position sensor. On a 4.7 it is just above the starter, on a 4.0 it is on the left side of center of the bell housing. The modules all communicate on the bus and if it is down the vehicle won't start. I've seen the crank sensor short out and pull the bus down resulting in the exact condition you described.

I can think of 2 possibles,it could be a bad battery cable or an intermitent short in the starter solenoid, check or have the battery cables and there connections on both ends first not only are they a cheaper fix but the problem you describe sounds like a current flow issue.Test them with or have them tested with an ohmmeter they should show o ohms resistance,and while not attributed to the problem I do not reccomend using Bosch spark plugs of any variety,the best plugs for any Japanese vehicle are NGK's,this comes from my personal experience with them and other techs that I have worked with.

I had a similar problem, it was my fuel and spedometer though. If you turn the car on and off a few times, they needles should go back to zero. The problem seems to be that they are physically worn and are getting stuck. I eventually had the instrument panel replaced for about $600 at a dealership because having to remember what speed it started at was too much of a pain. The car thinks that where ever it starts frmo is zero, so if I turned the car on and needle was stuck at 20mph then when it showed 65 I was really going 45. You may be able to live with those to gauges not resetting, I couldn't do it with the spedometer.