Wiring configuration

[wergittep]

I recently bought an old used Swiftsure boat, second hand. Everything seemed to work okay, until I was examing the wires under the dash, only to discover that two of the dash switches were not connected at all.

I have three switches. One says On/Off, the next one has no label (rubbed off I guess over time), and the third labelled P. The P switch is the bulge pump, and is wired and works great.

However, the other two switches - I have no idea what they are for. I know the lights on the front don't work, so I assume one of them is for those (although which one??), and I have no idea what the other one is for. My control box has a trim button, choke and starter, so the switches probably aren't for any one of those, unless the middle unlabeled switch has something to do with the Trim button).

Can anyone help me determine what they might be for? The motor runs well, and clearly doesn't need anything from the dash...unless there is supposed to be some sort of functionality from those that has been circumvented.

I would really appreciate any help that can be offered.

 

[Grandad]

Welcome to Iboats! Is this an outboard or I/O? First be aware that boats usually have 2 somewhat independent wiring systems. The logic is that the motor arrives from the manufacturer as a functional separate entity. The boat, depending upon size, may have been wired by the manufacturer taking advantage of the motor's wiring in that sometimes a positive and negative source is scrounged, perhaps near the ignition switch. As you suggested, likely one switch is for the inoperative lights and the other one could be almost anything from interior lighting to a windshield wiper that's no longer in place. I'd start by following wires to get the navigation lights working. As long as you don't have or need anything else, I'd treat the last switch as a spare for when you get inventive. - Grandad

 

[wergittep]

Okay, thanks Grandad for the suggestion. I should have mentioned that it is an outboard motor, but it works fine, so I don't see it as anything significant to the switches. I don't see any wipers (or even a hint that they existed at one time). This boat is from 1978, and is only 17 feet, so it's not like there's any cabin lights or the like. I don't see anything obvious for the two non-connected switches, which is what makes it confusing to me.

The nav lights will be easy, I think, but it will need to reach a power source, so I may have to run those wires to the battery at the back. I think what I will do is see what is connected to the battery, and trace them...that may offer some hint to what they may be for.

If only there was a way to get a Swiftsure manual...I can't seem to find one anywhere - and the company appears to be out of business.