" can" , also faults 43 & 44 are displayed when the communication lines have an issue. Could be shorted or open can wires, can wiring shorted to batt positive, or a bad display or controller. You'll need to test the can wires ( starting @ the controller - CA401 pins 3 & 4, follow thru CA501 pins 3 & 4, thru TB301 pins 3 & 4 which is the control cable connection, up to CA101 pins 5 & 6, to the display - CA701 pins 5 & 6. If the wiring tests ok, your looking at either the display or the controller.