500 Rubicon Meter-Shifting problem

Have a 2005 500 Rubicon. The meter will flashing D1, D2 ESP and will not display the gear I am in. Does not want to go when throttle is pushed. Will shut off, recycle and then it will work but will start flashing again if switched to 4 wheel drive or stop unit and let idol. I am sure it is a sensor but really do not know where to start. No owners manual, unit has always been serviced and is in great running order. Any input on this would be appreciated.