Radio draining battery in just hours?

[ster46]

Dual battery system. Welcaraft 180 Fisherman. Yamaha 4Stroke 115 Outboard.

The boat started strong, and I ran it for a 1/2 hour. Docked on an island, engine off, battery switch on "ALL". 3 Hours later, battery completely dead, needed to get towed in.

So yesterday I did some trouble shooting.

There was enough battery power to raise and lower the outboard.
I switched the battery switch to ALL and waited about 20 minutes. After poking around under the console, I noticed that the back of the Am/FM radio was HOT. Almost too hot to touch!!

Could this be something that could drain 2 batteries in a short amount of time?

So my plan now is to disconnect the radio, charge the batteries, then with the battery switch on "ALL", let it sit for several hours.

Any other recommendations? If the battery is still strong, then do you think I found the culprit?

Thanks.

 

[Silvertip]

Set switch to off, charge the batteries then set to 1, 2, or both and test. This assumes radio is connected to COM terminal on the switch and not directly to a battery.

 

[ondarvr]

0n another note, never set the switch to "both" when anchored and using stuff, the result can be just what you experience, unexpected dead batteries.

 

[Silvertip]

0n another note, never set the switch to "both" when anchored and using stuff, the result can be just what you experience, unexpected dead batteries.

Very sound advice, but if one looks at 10 installations of Dual Battery Switches one would find at least six or seven different configurations. And of those six or seven, at least one or two would be so outrageous that the switch position would be irrelevant. Lots of creative wiring done with these things.

 

[ster46]

0n another note, never set the switch to "both" when anchored and using stuff, the result can be just what you experience, unexpected dead batteries.

The thing is.... NOTHING was on. No bilge pumping, fish finder off. Radio Off, no running lights, nothing.

 

[spoilsofwar]

Ondarvr is right... I've always been taught "all" is only used for situations in which neither battery on its own has enough juice to crank the motor. If one battery is weaker then the other, the stronger battery attempts to charge the weaker one... Leaving you, potentially, with two weakish batteries.

The radio could be the cause, certainly. Heat doesn't come from nowhere; it is produced, in this case by electrical resistance, for whatever reason. I would proceed as you intend, with the radio disconnected, to test.

 

[bruceb58]

Unhook one of the battery terminals and connect your meter between the battery and the cable in current measuring mode and see what your current draw is. If there is some, start pulling fuses until you find what is causing the draw.

 

[Silvertip]

A radio that is too hot to touch is a clue perhaps? Unhook it and see what happens. Stop using ALL in your diagnosis. Use BAT 1, then BAT 2, then perhaps BOTH. If it turns out the problem exists only in BOTH, you likely have a wiring problem.

 

[Mo1]

Make sure the red wire on the stereo is connected to ignition and yellow wire to constant power

 

[bruceb58]

Make sure the red wire on the stereo is connected to ignition and yellow wire to constant power

You do NOT want the radio hooked to the ignition. Most of the time you want to listen to it with the ignition off. It should be hooked to a dedicated switch.

 

[merc_man]

I had smilar situation was out fish went to start boat half hour later to move and nothing. Had batteries to all. Did a little fiddling with batteries and i had one weak battery that was drainng the whole system. Turned week one off and boat fired up. Let run for a bit to make sure charged then shut off. Tried to restart ten min later with both batteries and dead again. Back to the one battery and all good. Just had to get new battery.

 

[bruceb58]

This is why you need a battery switch to separate batteries and never have it set to "both" unless for emergency start. You do not want one bad battery killing your other battery.

Use an ACR to charge both batteries and that way you never really need to set it to the "both" setting.