View Full Version : '04 Maristar low voltage alarm

07-18-2012, 10:39 PM
Hi All - spent a few hours researching threads before my post, but I need some help. This is a low voltage alarm issue when the engine is not running.

My Maristar is pretty stock. Only thing I've done is add 2 JL Audio e4300 amps and two tower speakers. Amps are wired direct to Perko (+) and battery (-) using #2 AWG. Been suffering with low battery alarm for years (including an MDC replacement in 2009), replaced batteries multiple times so I am pretty certain that is not the issuue.

Here's the details: initially ran 2 Optimas on a Perko switch (the big 34 series so i could run 'em all day). Had no problems for first several seasons, my boat is stored in my garage and I thought I was good in moritoring/charging those Optimas. Began getting low voltage alarm in 07/08 and the dealer said it was most likely my Optimas going bad. Got them tested and they were ok, butI did replace the Optimas with wet cells. Fine for beginning of '09 and the problem was back. Alarm going off with 12.2 volts at battery and under dash - so I replaced the MDC in fall of '09.

Last year, problem starts again and i limped through the season. So I start testing last week after installing a brand new battery. Low battery alarm:mad: - but here's the kicker - NOTHING running (stereo off and fuses pulled from amp power block) and the alarm goes off within 5-10 mins of turning on key (key in acc mode). If I am running stereo, I get 2-5 minutes (running one batt for now as I can't keep buying two!).

Figuring there had to be a short or abnormal draw, I got a clamp on ammete thinking that the above scenarios had to involve short of somekind. At rest with nothing on there is about a .25 amp draw, I can get about 10 minutes before the low voltage alarm sounds. With the stereo on at full volume the amps are drawing ~14-16 amps depending on how loud I crank it. In this scenario I get 2-5 minutes before the low voltage alarm goes off. Using two voltmeters and my 16 year old I can tell that have 12.4V at battery and 12.2 under the dash when the alarm goes off.

Read through as many posts as I can find and can't seem to get a handle on this. Dealer thinks another MDC is in order. Before I do that, can anyone think of something I may be missing?

Appreciate ya reading this far! Any comments are appreciated.