Was the battery disconnected recently then hooked back up? If so check to make sure all the power and grounds are hooked back up. Sounds crazy but this is often the source of these problems. If not check to see if the CB on the engine tripped. After that the options get worse with the MDC looking to be the culprit.
Also does the boat start? If so do you hear/see the gauges make an effort to boot (buzzing sound/needles shaking on the pegs)? If not we're back to ground/power and them MDC.