Battery help

[Captn TJ]

In my 280 I have 3 batteries. I left the charger on all night - this morning I tested all three batteries with a voltmeter (with the charger off). 2 of the batteries registered 13.2 and 1 battery which is on the house/starboard engine circuit) registered at 12.3 ( I turned off the battery switch so there was no load on the battery). I assume that battery is going bad? FYI the previous owner replaced all three at the same time.

Would that be your assumption?

 

[Craig]

Depends on how old they are. Generally best to do at least all in one bank at once.
Not mandatory though.

 

[Wylie_Tunes]

You first need to verify that the charge leg for that bank is supplying a charge.

 

[Little Ducky]

Need to really do a load test to see if a battery is failing.

 

[electricaldoctor]

It is best to disconnect your battery cables prior to testing each one individually to ascertain the state of each battery. You should also verify voltage from each charging leg of your charger as suggested in #3. Each leg may individually fused internally and it may be as simple as a blown fuse.