2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

RandyJ

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When I turn the key it's like there isn't even a battery in the boat. Jumped across the solenoid and it fired right up. All the fuses I found are good (checked with ohm meter). The switch checks out.. red to orange/yellow got continuity when switch turned to start position. The only thing I can think of might be the neutral safety switch unless I'm missing a fuse somewhere... anybody got suggestions? This motor is on a Triton 220 SL platinum pontoon boat with a binnacle control.
 

tdrudd87

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

Just a thought, bad solenoid? When you say "jumping across the solendoid", reminds me of starting old fords with a screwdriver, when the solendoid crapped out. The screwdriver bypasses the solenoid and gives power to the starter.

HTH,
Terry
 

RandyJ

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

ayuh... perzackly... the same trick my daddy taught me ... but normally a bad solenoid will "click".... This one appears to have a relay on a panel below the fuses on the motor. That is what I "jumped". It also appears to have a solenoid like on an old chevy starter. I'm assuming this is a Tohatsu built motor....
 
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RandyJ

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

... if I had a wiring diagram of this boat it might help.. not sure if all motors like this have the same wiring harness to switch and controls or not....
 
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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

most boats have a safety circuit to disable the starter. Maybe it thinks its in gear.
 

schematic

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

The relay you jumped has a brown wire which is fed from the key switch when cranking. Check for power when attempting to crank on this wire. There is a connector just off of the relay on this wire. Make sure its connected.


Safety neutral is built into the control.
 

RandyJ

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

The relay you jumped has a brown wire which is fed from the key switch when cranking. Check for power when attempting to crank on this wire. There is a connector just off of the relay on this wire. Make sure its connected.


Safety neutral is built into the control.

Yep... I know EXACTLY which wire you're talking about.. never could see where it went to and didn't want to tear into the motor on the water and lose the nuts & bolts in the 60 ft of water at the dock. I'm still betting on the safety neutral (yep, in the controls)... just got too late and too dark to continue working on it... my glasses started fogging up too. :)
 

schematic

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

Don't disregard the relay either....it could be open circuit. Check for voltage to the brown wire.....
 

RandyJ

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

Don't disregard the relay either....it could be open circuit. Check for voltage to the brown wire.....
Definitely will.. just gotta either get a helper to turn the switch while I watch my volt meter or rig some gizmo to let me know whether or not it gets power when I turn the key switch.
 

schematic

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

I just replaced one that looks like that on a Nissan. It had a open circuit winding in the relay. Just rig a testlight across the black to brown so you can see it from the control. If you have power when cranking, the relay is likely bad.
 

1nebel0

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

That is a Yamaha motor........
 

RandyJ

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

Was back on the job today.... definitely the relay. I wrote the number down (somewhere)... no doubt it is on many different brands of motors. It was made in Indonesia...
 

schematic

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

If you have the room, you could substitute it with something else. You may find its overpriced because of its size.
 

RandyJ

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

If you have the room, you could substitute it with something else. You may find its overpriced because of its size.
If it were one of my old junkers I'd definitely throw an old ford or riding lawn mower type solenoid on it for $15 but it is for someone else on his late model pretty & shiny high class pontoon boat....
 

MH Hawker

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

Boat motor solenoid are a bit different, their sealed to prevent a sparks and a fire. So using a car type is a very bad idea.
 

schematic

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Re: 2005 Mercury 115 4-stroke, won't crank.. no power to solenoid.

I was thinking of a Sierra 18-5816 if you have room.
 

Bigmikanthony97

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Oct 29, 2022
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Hello I'm having the same problem I have a 115 mercury and from ignition to safety has power but other wire has ground , if I disconnect harness itself the wire still has ground and help or idea
 
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