I can crank my boat but nothing else that runs off of the main power will work. Nav lights, trolling motor,etc?

-My boat cranks but anything that runs off of power wont work. Such as my nav lights, trolling motor, interior lights, and bilge pump. I checked the fuses and they are fine, I tried to use a test light but there is a good chance i am not doing it right cause i cant get a light anywhere. Someone please help.most boats have a fuse block up near teh dash and that block has the main ground and power for most accessories. i'd suspect a loose connection on one of those main wires.



test light, clamp on negative or a good ground and tip to positive on teh battery, if the light still doesnt work and the battery isnt DEAD, the light is busted.

always test your test light before trying to use it to test other things.



but props on trying to use it. you cant always SEE that a fuse is blown, really gotta test or swap in a spare.
check the connection at the battery. Did you check the fuse with a continuity tester? fuses can blow at the ends but still look fine.

Is there a master power switch on the dash or near the + terminal of the battery
With a volt meter check the voltage at the switch and see if it has power on both sides when turn on.