2016 G23 won't start

[Tallredrider]

Just wanted to educate myself as the boat goes to the dealer on Thursday. Boat is 2016 G23 with H6 and 305 hours.

Last week the boat wouldn't start one time. I jiggled the throttle, check the safety lanyard. Screen is on, start button just does nothing. It turns on the screen, but no click, doesn't turn over. It is just as if the boat is still in gear. I turn off the batteries, jiggle throttle again and start looking around wondering who will tow my 6 figure boat back to the dock. Then it started. Being a fool, I just hoped it was a computer glitch and let it go.

2 days ago was out and boat was running great and the same thing happened. This time lasted for longer and I was seriously about to start waving my long arms for help and got it to start after about 15 minutes. I didn't shut it off until we were on the trailer. Voltage reads fine, boat is running great otherwise. Cycling the batteries did not fix it. I think jiggling the throttle left and right (instead of forward and back) got it to start.

I get back to the garage and find that if I move the throttle just right, I can reproduce the no starting situation. It is definitely in neutral and clicks perfectly back into place, but with a gentle easing into neutral from reverse, it wouldn't start.

So something is definitely wrong with the throttle assembly. My dealer's tech mentioned some adjustment on the throttle that might be out, but I thought it was all by wire, and figured the whole throttle assembly has to be replaced since there seems to be a throttle position sensor issue. Unfortunately, I am a little sketched out with a big trip coming up to Lake Powell where getting stranded may literally be a safety issue. Maybe my tech was thinking about a 2014 which still had throttle by cable? I will make sure he teaches me how to adjust it so I can at least get back to the houseboat if I get stranded. The intermittent nature of the issue also makes it a little hard to diagnose, and I will for sure be frustrated if I get it in the shop and he can't reproduce it.

Is there anyway to safely 'hotwire' a boat with this issue?

On a side note, the button that allows you to rev the motor without putting it in gear has not worked for a long time...I keep forgetting to tell them about it. Doubt it is related, but wonder if anyone has an idea how to troubleshoot that.

[scottb7]

If I was to guess I think "the button that allows you to rev the motor without putting it in gear has not worked for a long time" is part of the issue. I think that just because they are "drive by wire" with throttle position sensors (which is by the motor), the gear shift shift lever still - i am guessing - has a neutral safety switch.

So what I am saying is that it is not recognizing your are in neutral so it won't let you start.

I don't know how you could bypass without pulling off some of the upholstery pieces in that area, finding the wires, etc.

You can borrow my g21 if you want.

p.s. is there a neutral safety switch on the vdrive? hmmm...not sure. no, i think it is throttle neutral safety switch issue.

[Tallredrider]

Good thought..although I think that what the button does is stops it from going into gear when you move the throttle...it might be interesting if it might have the capacity to make it stay in gear when it fails, thus disabling the starting. Although I have never had a problem putting the boat in neutral.

[scottb7]

I guess it could be the tranny switch also. You should be able to use a test light or multimeter to test this easy enough at the switch.

[Infinity]

Perhaps the fact that the Neutral button does not work....will convince them to replace the throttle assembly rather than "adjust" it!

[GMLIII]

Just wanted to educate myself as the boat goes to the dealer on Thursday. Boat is 2016 G23 with H6 and 305 hours.

Last week the boat wouldn't start one time. I jiggled the throttle, check the safety lanyard. Screen is on, start button just does nothing. It turns on the screen, but no click, doesn't turn over. It is just as if the boat is still in gear. I turn off the batteries, jiggle throttle again and start looking around wondering who will tow my 6 figure boat back to the dock. Then it started. Being a fool, I just hoped it was a computer glitch and let it go.

2 days ago was out and boat was running great and the same thing happened. This time lasted for longer and I was seriously about to start waving my long arms for help and got it to start after about 15 minutes. I didn't shut it off until we were on the trailer. Voltage reads fine, boat is running great otherwise. Cycling the batteries did not fix it. I think jiggling the throttle left and right (instead of forward and back) got it to start.

I get back to the garage and find that if I move the throttle just right, I can reproduce the no starting situation. It is definitely in neutral and clicks perfectly back into place, but with a gentle easing into neutral from reverse, it wouldn't start.

So something is definitely wrong with the throttle assembly. My dealer's tech mentioned some adjustment on the throttle that might be out, but I thought it was all by wire, and figured the whole throttle assembly has to be replaced since there seems to be a throttle position sensor issue. Unfortunately, I am a little sketched out with a big trip coming up to Lake Powell where getting stranded may literally be a safety issue. Maybe my tech was thinking about a 2014 which still had throttle by wire? I will make sure he teaches me how to adjust it so I can at least get back to the houseboat if I get stranded. The intermittent nature of the issue also makes it a little hard to diagnose, and I will for sure be frustrated if I get it in the shop and he can't reproduce it.

Is there anyway to safely 'hotwire' a boat with this issue?

On a side note, the button that allows you to rev the motor without putting it in gear has not worked for a long time...I keep forgetting to tell them about it. Doubt it is related, but wonder if anyone has an idea how to troubleshoot that.

Tallredrider this has happened to my 2017 G23 once. Please keep us posted once you discover the issue. Seems like it might be a common problem for Nautique

[Kmayotte]

Just for complete info for you, the issue with my 2016 not starting was due to a short in the transducer (for depth and water temp) that needed to be replaced. Apparently in 2016 and 2017 a lot of the accessories are wired through the ignition. So if there's a fault on any accessory on this circuit, the ignition doesn't work. They rewired in 2018 to get these accessories off the ignition.

By chance is the blue light on the leftside of the keypad blinking quickly? If so there's a fault somewhere affecting the ignition.

[GMLIII]

Just for complete info for you, the issue with my 2016 not starting was due to a short in the transducer (for depth and water temp) that needed to be replaced. Apparently in 2016 and 2017 a lot of the accessories are wired through the ignition. So if there's a fault on any accessory on this circuit, the ignition doesn't work. They rewired in 2018 to get these accessories off the ignition.

By chance is the blue light on the leftside of the keypad blinking quickly? If so there's a fault somewhere affecting the ignition.

Good to know

[Tallredrider]

Just for complete info for you, the issue with my 2016 not starting was due to a short in the transducer (for depth and water temp) that needed to be replaced. Apparently in 2016 and 2017 a lot of the accessories are wired through the ignition. So if there's a fault on any accessory on this circuit, the ignition doesn't work. They rewired in 2018 to get these accessories off the ignition.

By chance is the blue light on the leftside of the keypad blinking quickly? If so there's a fault somewhere affecting the ignition.

Was your depth gauge was not reading correctly? That is good information. If you had known, could you have just disconnected the wires to the accessory with the fault and the boat would have started?

I will see if I can check for the blinking light, although I think I likely have a different issue since I can reproduce it at least some of the time with throttle manipulation.

[Kmayotte]

Yeah the throttle manipulation is pretty weird.

Everything was working fine until the boat went dead abruptly. Had no idea what was wrong with it so can't say if disconnecting the transducer would have let the boat run. Good idea in theory but I had nothing telling me that's where the problem was. The tech at the dealer was able to find the issue quickly because info they had remembered from a nautique seminar about the issue. He knows I'm fairly good at self diagnosis on boat issues but told me I had little chance at figuring this one out on my own.

[Tallredrider]

I got a call from the dealer tech today. Adjusting the throttle did not fix the problem. He says that the entire throttle assembly needs to be replaced. Also noted when he was able to get it to start that the transmission disengage button was not working for him either. He thinks that those are probably related, and that button going out was a sign the throttle assembly was going out. I am not sure how it's all connected, but just figured I would put that out there too.

[GMLIII]

I got a call from the dealer tech today. Adjusting the throttle did not fix the problem. He says that the entire throttle assembly needs to be replaced. Also noted when he was able to get it to start that the transmission disengage button was not working for him either. He thinks that those are probably related, and that button going out was a sign the throttle assembly was going out. I am not sure how it's all connected, but just figured I would put that out there too.

Please keep us posted because I think I have the same problem on my 2017 G23

[Joeylabau]

I had the same issue on my 16 G 23 turns out that a relay was totally cooked. The dealer replaced the relay. next time I took it out I had the same issue, relay burnt out again along with ignition wires I believe, Took it back and they replaced all of it and no issues. Put about 200 hours since then


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[Tallredrider]

I had the same issue on my 16 G 23 turns out that a relay was totally cooked. The dealer replaced the relay. next time I took it out I had the same issue, relay burnt out again along with ignition wires I believe, Took it back and they replaced all of it and no issues. Put about 200 hours since then


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Were your symptoms the same? You could jiggle the throttle and cause it to start with the relay issue?

[Jim Foley]

How about some advice on a slightly different issue. My 2018 GS 20 has 26 hours, on 3rd tank of gas, and it turns over, but will not start without 25 + attempts. It cranks fine, sputters, then goes back to cranking with no turning over. I noticed this @6 hours, but it was sporadic then...more frequent @15 hours, now it just does not start...or if it does, it dies within 20 seconds. Dealer suggests looking at the 2 fuel filters...but I see from other posts getting them off and back on can be a challenge. I’m pulling the boat and taking to my local shop (dealer is 2 hours away) and would like to give some guidance if others have experienced the same thing.