DF 140 rev light stays on.

[tailfisher]

Hello, Last time I used boat everything was running good, have not had boat out in several months do to weather or work so today I hooked up water hose on muffs and started motor and noticed rev light stayed on in gauge. What would cause this problem and is it a simple fix. motor idling good. Any help will be greatly appreciated

[tailfisher]

can someone please give me some kind of idea what to check. Any help would greatly be appreciated.