bad battery? onboard charger not working?

R

rooster4

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May 9, 2009
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11
i have a 24 volt trolling motor, 2 batteries for that and 1 cranking battery. the onboard charger is connected to the 2 trolling batteries. how can i tell if one of the batteries is bad, or if one side of the charger is not working? i have charged the batteries with a battery charger and one is showing on multimeter 12.5 and the other is 12.8.

How long should it take to charge the batteries with the onboard charger?

I took the boat out for the first time, ran the trolling batteries down in a couple of hours, came home, plugged the boat in, the onboard charger on one side will give a green light, the other flashes red lights. went out the next day and didn't very much power in the trolling motor, acts like it is only gettting half the juice it needs.

it is a 2000 model triton, and the onboard charger shows to be a triton?
 
fixb52s

fixb52s

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Re: bad battery? onboard charger not working?

How old are the batteries?
Take the batteries out and have them tested. You could have a bad cell. I found some batteries that might show 12.5 volts, only to have them fail with a load.

Is the electrolyte at the proper level? Sometimes it will boil off while charging. Fill it with some distilled water and try again. Jut note that if it has dropped below the plates, the battery could be damaged.
 
K

Knightgang

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Re: bad battery? onboard charger not working?

I also vote for pull them and take them to be tested. they shoul dnever be checked while hooked up together.

12.5 and 12.8 is not a huge difference, but it could indicate a bad battery...
 
2

204Angler

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Re: bad battery? onboard charger not working?

One of your batteries will fail a load test. Batteries can charge fully but if they have a bad cell they will drain almost instantly with any amperage draw
 
Silvertip

Silvertip

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Re: bad battery? onboard charger not working?

To test the charger simply measure the output voltage with a voltmeter while the unit is connected to the batteries and the charger is plugged in. anything less than 13 volts says the charger is not working. If either output measure zero that says an inline fuse or breaker is open. Before you take the battery in for load testing, make sure it has been on the charger. How long it takes to charge a battery depends on the output capacity (output amperage) of the charger. Battery connections are also prime suspects when electrical problems arise. Disconnect all of them (one at a time) and thoroughly clean each. Securely tighten the connection and move to the next.
 
bruceb58

bruceb58

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Re: bad battery? onboard charger not working?

Silvertip said:
To test the charger simply measure the output voltage with a voltmeter while the unit is connected to the batteries and the charger is plugged in. anything less than 13 volts says the charger is not working.
Click to expand...
Not quite correct. If the battery was bad and had a shorted cell, the battery charger may not have enough current capablity to get the voltage above 13V. If you have a known good battery, attach it to the charger and measure the voltage.
 
A

Allmand Boats

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Oct 22, 2009
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Re: bad battery? onboard charger not working?

rooster4 said:
i have a 24 volt trolling motor, 2 batteries for that and 1 cranking battery. the onboard charger is connected to the 2 trolling batteries. how can i tell if one of the batteries is bad, or if one side of the charger is not working? i have charged the batteries with a battery charger and one is showing on multimeter 12.5 and the other is 12.8.

How long should it take to charge the batteries with the onboard charger?

I took the boat out for the first time, ran the trolling batteries down in a couple of hours, came home, plugged the boat in, the onboard charger on one side will give a green light, the other flashes red lights. went out the next day and didn't very much power in the trolling motor, acts like it is only gettting half the juice it needs.

it is a 2000 model triton, and the onboard charger shows to be a triton?
Click to expand...

I recommend you to use Minn Kota? On-Board Battery Chargers

Minn Kota's line of on-board chargers delivers performance-matched power to get the most out of your trolling motor system.
 
bruceb58

bruceb58

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Re: bad battery? onboard charger not working?

Allmand Boats said:
I recommend you to use Minn Kota? On-Board Battery Chargers

Minn Kota's line of on-board chargers delivers performance-matched power to get the most out of your trolling motor system.
Click to expand...
Oh brother! Pasted right out of theBass Pro advertisement.

Question...what is performance-matched power?
 
Silvertip

Silvertip

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Re: bad battery? onboard charger not working?

I agree that bad cell(s) may not allow the charger to get to 13+ volts but it is an indication that the charger is working, or at least trying to. You also do not get a valid load test if the battery has not been on a charger -- bad cell(s) or not. Testing this charging system has to be broken down to batteries, wiring, or charger. Testing on one part can be skewed by a fault in another so one needs to take that into consideration.
 
J

John_S

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Re: bad battery? onboard charger not working?

I don't know your charger or status light indicators, but usually green is good. ;)

With battery drained, when plugging in the charger, it should not have been in the green. If that is the case, I bet the inline fuse is blown for that one, or even disconnected.

Call Triton to get the manual that you need and follow advice that has already been given.
 
Silvertip

Silvertip

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Re: bad battery? onboard charger not working?

As was mentioned a number of times -- a battery can be put on a charger and the charger will show it is topped off (the green light comes on). If you were to measure the static voltage it would likely show 12.6 or so until you applied a load at which time the voltage drops like a rock. That's a bad battery. I have three tractor batteries on my bench right now. One has not been used for over two years since it was replaced with a new one at that time. Just for kicks I put a charger on it to see if it would come to life. Sure it does - but attach a load and it drops to 9 volts. That's what a load test does and why a battery must be charged (as much as it can be) before doing a load test. Doing a load test on a dead or discharged battery is sort of a waste of time.
 
J

John_S

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Re: bad battery? onboard charger not working?

rooster4 said:
I took the boat out for the first time, ran the trolling batteries down in a couple of hours, came home, plugged the boat in, the onboard charger on one side will give a green light, the other flashes red lights. went out the next day and didn't very much power in the trolling motor, acts like it is only gettting half the juice it needs.
Click to expand...

No way one bank should be green after two hours of use. The Guest chargers (two different models) I have, show green if not attached to battery or inline fuse is blown. The lights on the charger indicate charging rate, not the output of the battery.

The flashing red may be normal for his charger, maybe indicating max current draw?
 
P

ProMarJim

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Aug 26, 2009
Messages
14
Re: bad battery? onboard charger not working?

I would recommend starting here.

What charger do you have?

How old are the batteries?

Are the connections clean and tight to the batteries?

Have you checked the in line fuses?

Jim
 
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