230ma draw draining batt 2

[Eddie B]

Hi friends. I’ve been struggling with my batt 2 charge level. 2 new interstate batteries installed in April. Boat sat in water for two weeks or so and the charge on batt 2 went way dow to where it would not start the engine. I ran her for a while and she is back up to 11.5. Batt 1 is at 12.5. I measured the draw. Batt 1 is 0ma. Batt 2 is around 230ma even with all DC breakers off and the battery switch off. She is a 2003 240DA so only 2 batteries with a 1,2, both, off switch. I keep the switch off when not using. I do not keep her on a charger while at the dock. Is this a normal draw with all breakers off? How can I find the culprit? Could it be the Mercathode which I replaced in march? Trim pump is hooked up to batt 1. There is a little water accumulation in the bilge over the last 7weeks but not enough to trigger the pump regularly. This small drain over time is enough to drain the battery dead. This happened to me last year as well on a different set of batteries. Everything is stock except for the garmin which was not plugged in when I tested.

 

[Lazy Daze]

Regardless of the battery switch, the Mercathode will always draw a tiny bit. ECM will, as well. Possibly your stereo memory and maybe a bilge pump float switch (depending on style). BUT... start pulling fuses one at a time while monitoring amp draw.

 

[Eddie B]

Thanks Lazy. You always come through. Stereo memory is in the DC breaker which I turned off. I replaced the float switch this year. So maybe this is just the ECM and Mercathode? Why just batt 2? I have been pouring over the wiring diagram trying to figure that one out.

milk pull fuses and diagnose later this week. All fuses are under the helm? I can probably skip all the ones that are attached to the peanut pad (accessory switches on the helm) cause that whole module shuts down with the batt switch as far as I can tell.

mid 240ma more than you would expect Mercathode and ecm to pull?

 

[Highliner]

240ma seems way too high with everything off. As mentioned, pulling fuses while monitoring draw should narrow it down. Given this occurs with the battery switch off, pay attention to any system "additions" in the form of wires connected directly to the batty posts other than the main cables as well.

 

[paulswagelock]

How are you measuring the draw, specifically where did you connect?
Since it happens when the switch is off, no need to pull fuses. There is at least one wire going directly to battery 2 or the post on the battery switch where battery 2 connects. Find that wire(s) and that is your 230ma.

 

[spikedaddy99]

Stereo memory would probably bypass the battery off switch unless you have to reset channels every time you turn it on. 11.5 isn't back up to full charge on battery 2. Hopefully our electrical gurus will chime in here, but as Paul said, look for wires directly to the battery and start there. PO could have added something. Also get them load tested. Easy to do to rule out a bad (although new) battery.