2008 ford crown victoria instrument clustor issue

hey guys, new here but long time crown vic owner. i have an issue with my 2008 crown victoria instrument cluster being inoperative. all the lights are on; check engine, abs, airbag, tire monitor and they all came on at once. the odometer has dashes now and the speedometer is inoperative. any idea what causes this to happen? i fixed it before by disconnecting the battery and the reconnecting and it went away on its own for about 50-60 miles (drive cycle). passed inspection and on my way back it happend. i took it to my mechanic and had him hook up his snap on scanner and he said he counldnt read the computer because it wasnt sending any messages. any help is greatly appreciated

Better start checking for bad/corroded connectors. Some of those plugs over the years get moisture and will stop making a good contact. And with the new equipment, it doesn't take much to stop the circuit from flowing.

Start with a wiring diagram, and at every plug for the instrument cluster, disconnect and re-connect. And keep working from there.