Need Help. Wiring vs guages vs sending unit,

[BlueeyedRuss]

I just bought a 2011 stingray that is in great shape. I was aware when I bought it that the fuel guage was and the horn was not working. After buying it I also noticed the temp guage was off. Both the fuel guage and the temp guage are staying maxed out to the far right of guage no matter what. Tankf full or empty, temp hot or cold, the horn also not working. I read it could be a bad guage, bad sending unit, or could be just grounded. I just took a quick look at the wiring and found that the horn did not appear to be wired at all. I also took a look at the fuel sending unit and found the wires to be crossed (black to pink and pink to black) I did correct that but there was no change in guage reading. Do to the expensive of the boat purchase I am trying to repair this myself but not sure which way to start. The boat has had a wake tower with speakers and lighting added, and since both guages and horn are not working I can help but wonder if maybe there was a wire incorrectly connected. Looked at wiring hoping there would be something obviouse but it was def not obviouse, lol. II have done a little auto work in the past but my carear is medical so this is new to me. Hoping someone could either walk me through testing things and making repairs or could point me in the right direction to find guidance on it. Thanks in advance.

 

[NYBo]

Welcome to iboats!:welcome:

The gauge problem is likely a bad negative connection ("ground"). The horn problem could be related if they share a negative connection point, like the negative bus behind the instrument panel.

 

[crb478]

I would clean up all the grounds on the buss bar and then all the positive connections. Really I would look over the general condition on the wiring, if it looks bad I would consider rewiring it. If it looks ok I would trace all the circuits to make sure they are connected like they are supposed to be. If the Wake tower and speaker are new add ons I would make sure that they got a properly sized dedicated circuit to run off of, and adequate sized wiring.