[Eddie]

Just pulled boat out of winter storage and installed battery, went to make sure everything worked and some crazy things happen. When you turn on any accessory the accessory is underpowered, the fuel gauge drops and some of the control panel switches light up as if they are also on. Replaced all terminal lugs at battery, checked main harness from engine to back of panel, " Good ground and power". I see that the control switches are in series. Each switch is getting 12 volts and grounds are all ohms checking O.K. It seems like I have a cross short somewhere! Anyone up for the challange????? Also the power seat and the power motor for the sun deck also causes the same issues.

[anthonybradley]

Sounds like a grounding fault. Nort sure of the electrical layout of your boat but there are probabley a few negative bus bars withing it, check each of these etc. Basically check every negative connection you can find. With the power switched off you could use a multi meter with one lead going to the negative terminal of the battery and the other to various pioints such as engine block, bus bars etc and check for high resistance. Of course they can appear low resistance till you try to put current thru them but thats complicating it...

Ants

[Eddie]

Connected a ground wire directly from battery and checked all the black wires behined the dash, all are good. Something wierd is happening though! For fun I put the multi meter on volts and checked each ground and I am getting .003-.008 volts on the ground side whenever I turn any of the switches on. All grounds get the same reading because they are in series. Also the volts at the battery are 12.6 volts and the voltage behind the dash is 14.8 volts.

[anthonybradley]

Originally Posted by Eddie

Also the volts at the battery are 12.6 volts and the voltage behind the dash is 14.8 volts.

14.8v is quite high, I presume this is with the engine running? This is the top voltage I would expect to see from the alternator. Did you check the voltage of both batteries? I.e. the battery you have selected from the 1/2/both switch would be at about 14v with the engine running and the alternator charging it, and the other battery not selected will be at its more typical terminal voltage of 12.3-12.7v.

The dash is typically powered by the engine loom, so will likley be the alternator voltage regardless of which battery is selected. If you are not getting the 14v on either battery with the engione running then there is a problem with the charging ciruit.

Please let us know some more detail.

Ants

[Eddie]

With engine off. I have only one battery hooked up with the three way switch selected to that battery. The positive cable is going from the battery to the switch to the starter then comes from there to the top of the engine block and runs through the main wire harness up to the dash. The ground is comeing from the battery to the engine and up through the engine wire harness to the dash. With the engine not running I am getting a good ground and 12.4 volts at the end of the main wire harness at the dash. However with the harness plugged in and I check the backside of each switch I am getting the 14.8ish volts and a good ground. I am also getting a reading of .003 to .008 volts on the ground side of the switch with the switch activated. This happens on all switches. In return no matter what switch is activated they all light up and there is a significant power lose to the activated component. As far as I can tell only one componant runs at a time but every light for all switches light up. Hope this helps.

[anthonybradley]

So you are measuring 14.8v with the engine off? Any battery chargers plugged in? if no to both then you should not be getting 14.8v anywhere.

So whatever switch you turn on all teh indicator lights in that bank of switches light up? Have you tried temporarily running a cable from battery negative post to the negative connections on the back of the switches? What teh voltage at the output terminal of a switch when its on vs when its off. measure it furst using the negative connection on the switch, then using negative direct to the battery (with a bit of wire if needs be).

Ants

[Eddie]

Yes all teh indicator lights in all banks of switches light up. No chargers on. I disconnected the ground from one of the switches and connected a ground strait from the battery. Symptoms still there. 14.8 volts on hot wire and 14.8 volts on supply wire to component when switch turned on.

[Eddie]

Found it! GROUND block behind battery has numerous ground wires and one was broke!!!!

[anthonybradley]

Great well done, i knew it had to be a ground fault somewhere.

Ants

[stereoman405]

I'm currently experiencing the EXACT same issue. That smaller ground block appeared to be okay when I was in there. Are there any other ground blocks to check out?

EDIT: I started a new thread to keep it organized.

http://www.mariahownersclub.com/foru...4023#post14023