Can anyone help me figure out why my trim gauge dont work??The gauge is new.the sender on the outdrive is new.The only piece left that i know of is the little black box on the transom that the sender plugs in to.When you turn the key on the gauge floors its self??? Any help please.

I assume you have bravos. Sounds shorted to me. Disconnect the sender wires from the gauge. It should read max and min with the circuit open or shorted. That will prove the needle will sweep the full range. I imagine the gauge isn't the problem (although even with a new part, it is a slight possibility). The wires frequently chaffe where they pass through the transom assembly.

I meter out the wire from the gauge to the plug on the box on the transon and they where ok. I have power going in to said box but nothing coming out is that right???And yes it has a bravo. Thanx for any help this thing is killing me.

Not to thread jack on my first post, but I just picked up a Mirage 257 with a repower 496 and have the same problem.

Ground out the gauge, full sweep, gauge doesn't seem to be problem. Here are some pics from the back.

If this is non-related issue, let me know and I'll get off your thread!

Regards-

I found my problem to be that the black box on the transom was bad.Not sure of the name of the box.