help with boat trim, engine rpm, and fuel gage

[red rock cod]

having trouble with all 3.

boat trim gage seems to be constantly reading up posn even tho motor is down

engine rpm stuck on about 1400

fuel gage reads between full and 3/4 no matter how much fuel is on board. tank is 200 litre.

engine jonno 4 sroke 140 hp ocean pro. [suziki]

help please to get gages to read correctly.

[FishHunter]

Sounds to me like the guages are either not getting power or ground or are not connected to motor. Start by checking the power supply to the guages with the key on 1 of the wires should have 12v I think its the purple if that chwecks out make sure the black wire has a decent earth at most 2 ohms.

The fuel guage sender unit or guage could be faulty take the wire off the sender and if its a single wire short it to ground if 2 wires bridge them out the guage should go to the full position if it doesnt its a wiring or guage issue if it dies then the sender is faulty.