2002 Air electrical fault

My wife and I purchased a 2002 Air Nautique with 300 hours earlier this summer, have really enjoyed the boat so far. Unfortunately we had an electrical issue rear its head the other day after about 20 hours of use this summer. When leaving the dock I went to turn on the blower, as soon as I engaged the switch I lost power to the majority of gauges and accessories. The temp and oil pressure gauges remained, but all other gauges, head unit, and accessories lost power. I attempted to cycle power with the Perko switch, this temporarily rectified the issue but after testing the horn button (horn made about 1/3 the sound of normal, possibly not getting full voltage?) the loss of power returned. Repeated this cycle a few times; turning the key off, cycle the perko switch to off, then 1 (or 2) battery, then restart the boat. When there is no power to the gauges I can I hear feedback from the subwoofer and the fuel pump prime, even with the key in the off position. The check engine light is also partially illuminated regardless of key position. Eventually I was no longer able to turn the boat off with the key, no matter what position the key was in the engine remained running. This led me to believe it might be an ignition switch issue, so I purchased and installed a Sierra switch, unfortunately that did not solve the problem.

I have pulled the dash away to check for loose wiring, have tightened and wiggled connections on the gauges and switches but nothing permanently resolved the issue. At the advice of a local independent repair shop I checked the main battery fuse for corrosion and attempted to reset the breaker, neither made any change in the symptoms. It appears that the issue (guessing loose wire or short) is either behind or underneath the dash. I say this because when I manipulate the harness under the dash the issues comes and goes, especially when working around the fuse block.

I have searched and read lots of threads but not found any that appear to be related to my issue. The boat is a 2002 Air SE. I have a keyed ignition, not the keypad. The boat had a myriad of accessories installed by the original owner (heater, sound system, tower lights, docking lights, shower, depth finder, etc.) so unfortunately there has been several different installers crimping onto wires and messing with things over the years.

The battery cables have been checked, new Interstate deep cycle battery was installed approximately a month ago (second battery was still holding charge, Optima). I have only set the Perko switch to position 1 or 2 since the new battery install for fear of causing an issue with the mixed chemistry batteries running in parallel. Engine is an Excalibur. All connections behind the dash have been checked for shorts/loose connections. I opened the dash and was a bit shocked at the rats nest of wiring, very little appeared to be factory which led me to believe maybe the gauges had been replaced previously due to a digital gauge failure. The original owner claimed the boat came from the dealer with analog gauges installed.

Sorry for long post and creating a new thread on an issue that has likely been covered in the archives. I have done lots of searching here and on other Nautique forum. We have a lakefront cabin reserved for a 3 day weekend starting on the 17th. I would be happy to pay somebody to repair, no appointments available. It is down to me fixing the issue myself or not bringing the boat on vacation. Please help!!

This all kinda sounds like a bad ground on something, either the original stuff or some of the things that were added before you got the boat.

Bad ground is what I am thinking as well, I’m finding that locating the grounding points is more difficult on a fiberglass boat than it is on the old cars I normally work on! Can anybody tell me where I can find a wiring diagram for this boat or similar? Is it possible that the bad ground is on the fuse block? I just spent a couple more hours searching and have noticed some loose terminals on the port side of the fuse block. The fuse block is available from Nautique Parts, I hate to be a “parts swapper” but that tends to be my default when chasing electrical gremlins.

Appreciate your insight Keno and 63skier, helpful to have people who know Nautiques to bounce ideas off of.

[QUOTE=02Air]s because when I manipulate the harness under the dash the issues comes and goes, especially when working around the fuse block.



new Interstate deep cycle battery was installed approximately a month ago (second battery was still holding charge, Optima). I have only set the Perko switch to position 1 or 2 since the new battery install for fear of causing an issue with the mixed chemistry batteries running in parallel.