This is just too general a question to answer. Your first resource should be your owners manual. If you don't have one, use the Google search form to the right to find one for your boat's make and model. There are a variety of places that sell them. Added answer- boats tend to not have manuals specifically for dash wiring, etc. But they tend to be more straight forward than autos, so you generally take a step by step approach using normal troubleshooting procedures. A good place for info is a good boating forum like iboats.com.
There are certain car gauges which are mandatory to have in a dashboard. These gauges are the speedometer, the temperature gauge, the fuel gauge, the tachometer, oil pressure gauge, charging system gauge, and odometer.
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How do you reset dashboard brake light on vw passat
How do you reset dashboard codes for 2000 Cadillac STS?
check the fuse panel and the fuses
Check for a blown fuse.
It's that part in front of the driver with the lights and gauges, radio, glove compartment, etc.
reset the brakelamp light on the dashboard - Honda prelude 1991
How do I Reset dashboard warning lights on 90 Lexus ES250
Bad light bulbs.... Replace them...
Faulty wiring, faulty CECU.
There is no reset for a check gauges light. If the light is on, there is a problem either with the temperature oil pressure or voltage.