Looking for some help with a trim position issue I am having.... Gauge was working good earlier last summer but then intermittently stopped working. Then would start working at times but only on a fresh start and idling... I thought it was maybe a bad guage, so I replaced it and still had the same issue. Intermittently working.
Did some searching online and seems to lead to the sending unit....
Any thoughts on this? Any other possibilities I should look into? And if it is the sending unit any tips, info and DIYs on how to do it??

I'm going back a few years but if you pull the sending unit off and move the dial manually and have somebody watch the gauge to see if it moves accordingly. While off make sure the gimble bolt is tight and not lose at all. That use to happen frequently back in the day. There isn't much else it could be unless you have a corroded wire connection but I doubt it. Check the gimble bolt behind the sending unit. Large Allen headed bolt that the back of the sending unit fits into. If the bolt is lose at all it will move along with the back of the sending unit and sometimes not, giving you false readings or none at all.

the sending unit sits in the water when the boat is not moving,water&electrical parts don,t play good .

I use to pack with electrode grease but still have seen them destroyed in a short time. Not an ideal design considering. Once you go mechanical you never go back.

If the gauge goes from reading normally to full up ( like when the ignition is off) look for breaks in the 2 wires going to the senders, if it's inconsistent movement, check for a loose hinge pin as mentioned earlier.

Trim limit switch is done. You can order the internal part to try and fix it. If that doesn't work then it's time for a new one. Just had mine replaced this week. I tried the internal part replace and worked for one boat ride. Last ride gimbal bolt was starting to get loose and backed out enough to bust the puck off. Glad it did. Corrected gimbal bolt issue and had a new limit switch put on.

Not a two minute fix. To do it right you have to pull the drive and bellow to thread the three wires.

Thanks for all of the replies.... Im trying to remember exactly what caused it to stop working and/or start working again... boat is in storage and havent used it since October. If I am remembering correctly there was a time that it wouldnt work, but once I got the drive up about 3/4 or almost all the way up, it would then shoot the gauge correctly. I think it would also work OK after a fresh start in the down position, but once getting up off idle (FOR SOME REASON I THINK) it would stop working.... Drives me nuts I cant remember exactly what it was doing.

At least now I got some ideas what to do... Ill have to do as getrdunn, jaayteee, and crownlpx and check the gimble bolt as well as have someone watch guage as I move the dial.
Ill also have to pack the sender with grease as you said getrdunn.... I came across one of you threads suggesting that earlier...

Appreciate all the help guys.... Just hope I dont have to pull the entire drive and bellows to replace these.... I HATE to pay people to work on my stuff if I can fix it myself.

I don't know what system you have, But work your drives in and out while you have someone watch them from outside to make sure the drives are moving correctly. It could be a electrical connection or cables binding or a low fluid level. Again don't know what setup you have.

Its a traditional bravo setup with the limit switch and sending units (electrical) on opposite sides of the gimble... with a Faria gauge on the dash. No issue with the drives going in/out.... just the gauge not working