Battery issue

[desertrat64]

2015 Thor 31W:
Trying to be as concise as possible:
1. House batteries were very low (realize they may be permanently damaged, but removed them and checked good.)
2. With shore power (switch to "use"), voltage at terminals was 13.6
3. Started coach, and voltage increased approx. .6V. Turned off coach, and voltage returned to previous reading.
4. Removed shore power and turned on inverter. Yellow light (battery) was illuminated, and voltage on display read 13.5V.
5. Voltage rapidly dropped (5 minutes?), and gen-set kicked in (auto-gen).
*** batteries were removed, and checked good***
*** voltage at battery terminals remained a bit above 13 7 hrs after removal***
Question.. does it seem a battery issue, or something more perplexing?
Thanks ahead of time

[16ACE27]

Battery issue.

What does "checked good" mean?

Was a measured load test performed?

I just replaced a chassis battery that measure 12.7 VDC hours after ir was removed from the coach. Then I connected a small inverter to it with no load and the inverter would not turn on and the battery voltage read 10.1 VDC: classic bad cell symptom.

[Bob Denman]

If you've got the batteries on a charging source: it's more accurate to wait about 10 minutes to check their voltage.
I believe you're seeing what has been referred to as a "surface charge".
When mine are hooked up, and I check their voltage immediately after unhooking them: I normally see 13.4 volts. If I wait 10 minutes: they always settle in at 12.8...

[desertrat64]

Thanks for the reply.. I took the batteries to auto zone to be checked, and re-installed them. I did ask if what they were using was a load test, and they said it was. All I have is a multi-meter.