I have just purchased a new boat which is my first boat and have a 24 volt trolling motor with a 3 bank on board charger. Which gives me two banks for the trolling motor batteries and one bank for my cranking battery. When I get back from a trip I put my batteries on the charger and let them charge. The charger shows that the all batteries are charging. I can get my cranking battery to full charge and one of my trolling motor batteries charged. No mater how long I leave my batteries hooked up it will not charge the one trolling motor battery but says it is charging. I know the charger is not charging because when I hook a amp probe on it it is not drawing a current. Has anyone come across this problem before? Also, the batteries are new.

Thanks for the help

I haven't had that problem. I would search for the chargers manufacture on the net and call their tech reps.

When you take the leads off the battery is there voltage present? Each set of leads has an in-line fuse in the positive lead. Have you checked to make sure it is intact?

This normally indicates a weak battery. If the charger lights are red it is charging. You may want to check the water levels if the cells are not sealed.............Al

BTW- You can not check amperage with the charger leads connected the battery, only voltage.

Simple and easy test: Switch the charger leads to the batteries to see if the "problem" transfers to another battery. If it does, one bank of the charger is bad. If the same battery still does not charge, it's a bad battery.

I was thinking it may be a week battery but they have only had two trips on them since I have purchased them. Al with the charger charging I can check the amps on the other two banks and they are close to 10 amps. I have a 30 amp charger with 10 amps per bank. I will check the water lvl of the batteries when I get home. Wayne I will try doing that tonight. I did check the fuse and they were good but it would not hurt to check them again.

Thanks for the help.

Just a thought-

If you bought it from a reputable dealer that's in your area, take it back. If it's a brand new boat, it's got warranty and that's part of why you paid so much extra for that new boat smell.

If it was a used boat, he should still stand behind it - the dealer may have installed the charger, batteries, etc. and may stand behind the workmanship or parts he installed. Just a simple phone call.

Unless you bought it privately or from a dealer a couple hours or more away, it's worth a call just in case that thing needs a new charger - he should have extras in his parts department for this exact scenario.

Good luck.

Just a thought-

If you bought it from a reputable dealer that's in your area, take it back. If it's a brand new boat, it's got warranty and that's part of why you paid so much extra for that new boat smell.

If it was a used boat, he should still stand behind it - the dealer may have installed the charger, batteries, etc. and may stand behind the workmanship or parts he installed. Just a simple phone call.

Unless you bought it privately or from a dealer a couple hours or more away, it's worth a call just in case that thing needs a new charger - he should have extras in his parts department for this exact scenario.

Good luck.

X2 No reason you should be dealing with an issue like that alone after buying it new.

Some very good ideas on how to isolate this problem.

    I'm sure you have a good warranty, so use it while it lasts.   

    There shouldn't be any corrosion with a new boat, but sometimes looses connections, a little corrosion, or the inline amp breaker could be tripped.