Low Voltage Alarm - Need Advise

[carolinagreenhead]

2015 Pro XS 200hp serial #2B111932

I had a low voltage alarm go off again. I had the same problem since I've had the boat. I thought it was caused by the stock battery (Interstate grp 27) not being able to handle the load. So during deer season, and since I wasn't running the boat, I put in a Sears PM-1 grp 31. I used the marine battery post connections like Don suggests.

That at brings me to today. The same alarm went off. My SmartCraft gauge was reading 11.2/11.3 volts on the STBD battery. It was reading that same voltage all day but didn't sound the alarm til 3:00 this afternoon.

So, I need some advise on what could be causing this now that I've excluded the battery. The boat and motor is still under warranty if there's a problem but this seems like something simple. Just can't put my finger on it.

Mr. Weed please chime in when you can please sir.

[jrspop]

Starting battery? 11.3 is low voltage. It should read over 13 on the starting battery while engine running if it is charging properly.

[carolinagreenhead]

I've got the Minn Kota 345PC and I did change the profile on that bank to agm.

[jrspop]

That charger charges it 14.4, then float mode is 13.4. My agm start battery will dip below 13 when cranking, then well over 13 while running.

[EuropeanAM]

Shawn- confirm what your RUNNING voltage is (after 5 minute run). If your running voltage is not 12.9 or higher, you very likely have a charging system problem.

Multiple possibilities... some simple tests can confirm the cause.

We could sneak you in anytime Monday-Wednesday.

[carolinagreenhead]

Thanks Don. I'll give you a call Monday and we'll get something figured out.

[EuropeanAM]

Nice getting to spend a little time with you today- glad we were able to get it corrected so you can get out there on the water!

For those following the thread- Low Voltage condition caused by a blown Fusible Link (lead) on the Alternator Output Lead.

[JOE54]

isnt it 100 amp, what happened ?????

[Savage]

isnt it 100 amp, what happened ?????

My guess would be that the battery leads to the motor got crossed, or charger leads got crossed.

[carolinagreenhead]

Can't Thank you enough Don. The pleasure was all mine. As for what happened...don't really know. It's a problem I've had since I bought the boat new in May. Polarity got reversed somehow at some point.

Reminder - Torque spec cheat sheet

[EuropeanAM]

Definitely is caused by a reverse-polarity condition. Only takes a fraction of a second.

No telling "when" it happened... so there's no fingers to point. It just "did" happen somewhere, at some time (perhaps even while it was being rigged).

[Savage]

Amazing that the boat was even useable without having a functional charging system.

[billspence]

Another example of why this board is the best Mercury resource on the net. Thanks to Don and this Savage fellow. You guys are tops.

[Savage]

[carolinagreenhead]

Amazing that the boat was even useable without having a functional charging system.

Yeah, Don and I were talking about that very same thing. He said my battery has never received a charge so it's a wonder I never had to paddle.

[Savage]

Yeah, Don and I were talking about that very same thing. He said my battery has never received a charge so it's a wonder I never had to paddle.

True. You were only sustaining the batteries life via an onboard, or external charger. I would have been getting towed at the end of the first tournament, unless I ran to one spot only, and never caught a fish .

[carolinagreenhead]

True. You were only sustaining the batteries life via an onboard, or external charger. I would have been getting towed at the end of the first tournament, unless I ran to one spot only, and never caught a fish .

Shouldn't be an issue now.

[carolinagreenhead]

Last update:
Boat ran at 14.1 volts all day and ran like a champ.

[Z518 Comanche]

I take it, you didn't have to buy another battery?

[carolinagreenhead]

I take it, you didn't have to buy another battery?

Nope the battery seems fine. Ran strong all day. It wasn't getting a charge from the motor, just the charger.