No power to instruments or key

michaelkeb

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Jun 2, 2015
Messages
19
I recently reinstalled my motor and have hooked everything back up but now none of my instruments or switches work. The key dosent work the only thing that does is my trim tab switch. It's a 1985 bay liner with a 305 aq225d also a Volvo 280 out drive. Help
 

gm280

Supreme Mariner
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Jun 26, 2011
Messages
14,585
Go to the battery box and verify that is all connected and the fuses are good. Then using a meter, check for voltage at the fuse block. If you get voltage there, make certain you also have a good ground...
 

NYBo

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Oct 23, 2008
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7,107
There should be a fuse or circuit breaker mounted to the engine that protects the ignition circuit. The gauges are on this circuit also.
 

michaelkeb

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Jun 2, 2015
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ok I called a marine mechanic and he walked me thru it. there was power everyewhere except to my dash. he said the 14 guage red wire that goes from the circuit breaker on my engine to the key is probably broken somewhere in the harness and to run a new wire from the circuit breaker to the key switch. does this sound right?
 

UncleWillie

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Oct 18, 2011
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It is correct if...If...IF... There is power on one end of the wire and not on the the other end.
The chance that a 14 gauge wire broke in the middle is highly unlikely. Trace it out.
Confirm that the fuse is good on the aft end and and then actually locate the break before blindly replacing a cable that may not need replacing.
That cable is commonly 10 gage not 14! Double check it.
 

Grandad

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Jun 7, 2011
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I had this sort of problem once and discovered that the wire harness had come unplugged inside the sidewall near my 1972 Mercontrol. The Mercruiser setup in mine has an engine harness, a dashboard harness and a patch cord between. Although the patch cord to dashboard plug appeared to be intact, it had slipped out enough to lose contact. After re-installing it, I added a gear clamp around the waterproof boot on both plugs and that's kept everything together for about 10 years now. - Grandad
 

UncleWillie

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You're thinking of the fuse panel feed. He's referring to the ignition feed.


I am thinking that a RED Wire "...from the circuit breaker ... to the key" that causes none of the Instruments or switches on the dash to work, would be the 10 gauge panel feed.

... And that the 14 gauge Ignition wire, from the Key, back to the engine would have been PURPLE and the Dash Switches (NAV Lights, Horn, etc.) would still be working. Unless it were broken right near the key, the instruments would be working also.

Questions Abound! :joyous:
 

pantaloonz

Petty Officer 1st Class
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Nov 28, 2014
Messages
237
Good day!

Had the exact same issue on my 1992 Four Winns. Check the engine wiring diagram (if available) see if you have 50AMP fuses or circuit breakers.

Mine had two circuit breakers, one for the trim motor (which worked) the other. for EVERYTHING else. CB went dead, replaced.. runs great.

I diagnosed with a simple multimeter, power to one side of the circuit breaker, nothing on the other, button would NOT reset. When I took it apart one of the posts actually broke and green corroded metal could be seen all over it :)



-Pantz
 

NYBo

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Oct 23, 2008
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I am thinking that a RED Wire "...from the circuit breaker ... to the key" that causes none of the Instruments or switches on the dash to work, would be the 10 gauge panel feed.

... And that the 14 gauge Ignition wire, from the Key, back to the engine would have been PURPLE and the Dash Switches (NAV Lights, Horn, etc.) would still be working. Unless it were broken right near the key, the instruments would be working also.

Questions Abound! :joyous:
You missed the part about that circuit breaker being on the motor. He's saying his ignition and gauges don't work, which points to the motor circuit. The fact that his switches don't work points to the accessory circuit. In other words, there appears to be more than one problem on the + side OR there is a bad - connection, a.k.a. a bad ground. As I think about it, the latter may be the answer.
 

UncleWillie

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You missed the part about that circuit breaker being on the motor. He's saying his ignition and gauges don't work, which points to the motor circuit. The fact that his switches don't work points to the accessory circuit. In other words, there appears to be more than one problem on the + side OR there is a bad - connection, a.k.a. a bad ground. As I think about it, the latter may be the answer.
I will agree with that!
But, in as much as he just reinstalled the motor and nothing has worked since; I'll guess the problem is in the rear on the POS side of the Battery.
The trim motor has its own battery leads; explaining that it still operates.
If the battery POS to everything else is still lying loose, that would explain everything.
 

michaelkeb

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Jun 2, 2015
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the fuse on my motor has power to both sides but the red wire to the key switch has no power. so that must mean there is a break. i was told the red wire to the key switch comes straight from that fuse on the motor.(the one with the big red reset button on it) once i ran a wire from that fuse t0o my keyswitch the key turned on and my drive started working again going up and down. forgot to check the instruments but had to go back to work. how does this sound?
 

UncleWillie

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You need to trace that wire!
If there is a break, you will find it.
If there is another Fuse in the wire you will find it.
If there is a disconnected connector in the line, you will find it.

Do not consider the wire broken until you find the actual break.
Replacing wire on a hunch is bad technique. If you end up replacing the wire, remove the old one.
 

Grandad

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Jun 7, 2011
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I agree with Willie. Wires rarely "break". You'll likely find a poor connection where the terminals are loose or corroded. - Grandad
 

pantaloonz

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Nov 28, 2014
Messages
237
the fuse on my motor has power to both sides but the red wire to the key switch has no power. so that must mean there is a break. i was told the red wire to the key switch comes straight from that fuse on the motor.(the one with the big red reset button on it) once i ran a wire from that fuse t0o my keyswitch the key turned on and my drive started working again going up and down. forgot to check the instruments but had to go back to work. how does this sound?

Michael

This is sounding more and more like the problem I had with the being that your trim and ignition are not on the same circuit breaker. When you say the thing with the big red fuse on it.. do you have a pic of that? The big red button might be the circuit breaker. The circuit breaker itself may have failed?

I actually had a two circuit breaker setup, the incoming feed from the battery was all good to one, but the 2nd it was not going through it. If you used a wire to basically bypass this part..it makes sense to me it's that unit, or could you have a 2nd fuse, or breaker inline that's stopping you. I tend to agree that wires just don't break..

That being said, if there have been electric additions the line may have been tapped.. taped and then come loose. Still sounds fuse or circuit breaker related to me.

I think a pic might help.. does your have the large cannon type connector right at the fuse/circuit breaker assembly? everything all good there too?

-Pantz
 
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