bodowlab

Only 6 volts at fuse panel

12 posts in this topic

Hopefully the giant brains of this forum have an idea of what might be causing this. This is on a 2004 280 ssi. I'm only getting 6 volts at my fuse panel. This just started yesterday. All was fine before that. Anyway because of this, none of my helm switches work.  There are 12 volts coming out of what looks to be a transformer right above the battery switches and it looks like a wire from there goes to the fuse panel. I'm at a loss. I removed both grounds off the buss bar (I think) and tested each one and both are only showing 6 volts. The house and starboard battery were both old so I replaced both of those.

Any ideas or things to try. 

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Did the problem start after you replaced the batteries? If so, check all of your connections. Did you buy golf cart batteries??? 

Start at the batteries to check for nominal 12 volts. Work downstream from there, checking voltage at each connection. 

brick

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No, I replaced the batteries because of this. The place where I have the boat left the batteries on and killed them.  I jump started it and while it was running I noticed that none of my helm switches were working. I looked at the batteries and the house battery was old so I replaced that. Then the starboard engine wouldn't start with just it's own battery.  So with wishful thinking I replaced the starboard battery hoping it was just that.. Now both engines will start on just their own battery, but my helm switches still don't work.  I get 12 volts all the way out of the "transformer" but when it gets to the fuse panel I'm down to 6v.

I guess here is my main question. How do I go from 12v to 6v?  What would cause that or how can that even happen?

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NEED pictures of that TRANSFORMER.  Also all the writing on it.

Possibillity ?  A bilge pump or blower  is STALLED & pulling too much current for the wires. Fuse will not blow or a circuit will not trip.  The failed  part is connected possibly by a shorted on switch. Even if the switch is in the off position. Wiring has a under sized wire feeding the plus or minus buss bars.  It has now become a resistor with current flowing in it

 

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considering main power starts at the main starter post.and each engine should be isolated from each  we would need to know what engines you have installed

to get a wiring diagram.

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I thought about that I should've gotten pics as I was almost home. I'm 45 minutes from the boat so I won't be able to get the until next weekend.  I'll try to unhook power to the auto bilge and see if that fixes it.. That could be it. 

The engines are VP 5.7 Gi-E

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Your problem sounds like a bad connection, or a broken or corroded wire.  I'm thinking the "transformer" you're referring to is an automatic charging relay.  Spend some more time with a Voltmeter and a isolate the problem.  It would be helpful to have a longer test lead to go directly to the neg battery post.  Keep in mind that if you were checking voltage at the helm switches against the ground buss, the issue may be on the ground side of things.  

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I sure hope a " Automatic Charging Relay " is wired directly to the battery + & -  battery posts.

It is possible that the device / pump  has destroyed the Transformer. Or the transformer is reducing voltage & current to what it needs to . To protect itself. from a pump cooking away constantly.

Are the other batteries run down to 6 volts also by now ?

Turn OFF ALL big battery switches. does the 6 volts start to rise slowly or rapidly ?

Is the transformer very warm ?

Last check. Is the voltage lower than 6 volts now ?

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19 hours ago, brick said:

Did the problem start after you replaced the batteries? If so, check all of your connections. Did you buy golf cart batteries??? 

Start at the batteries to check for nominal 12 volts. Work downstream from there, checking voltage at each connection. 

brick

Yes, as brink said. Work your way to the helm with a volt meter. Meaning, trace each wire to every point and check. Even check your on board charger to see if that the problem. There should be no transformers in the D.C. wiring. Transformers only work with A.C.

 

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Ok, it looks like the forward bilge might be stuck on.  The helm stich shows the bilge is on even though the switch is off. The boat was in the sun last time so I wasn't able to see the light on the switch.  I looked for the forward bilge today but couldn't find it. Any idea on where it is or how to get to it?

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