Battery test still shows 11.9 even after three new batteries back to back with 13 volts shown on my

your post is a little confusing. how and why did you top off the hybrid battery? you got a hybrid battery from AAA?

what are you measuring the 12v with?

what 'same 12.4 volts?

 

What's important here mostly is that the readings from the device you're using are consistent so if your device at your house is reading your battery at 11.9 consistently then I would take that probably as being 12 volts that should not be causing you to replace the 12 volt battery You need to be down you know a complete vault or better not a couple of tenths. In my generation too with a very late model 12 volt and a new hybrid battery and all that nonsense I see 11.7 on the 12 volt all the time or pretty regularly when I do check it which is very rarely and everything is working fine I don't worry about 12.4 to 11.9 to me that's 12 volts and a little bit over that range that I just put above should be fine If you're only replacing batteries because of numbers you're seeing on a digital display of a tool that might not be such a thing.

 

I DO wish that people would put some white space in their posts.

Like this.

It makes them easier to read and understand.

How exactly are you getting those voltage readings ?
And where are you making the connections ??

IF......you are measuring directly on the battery posts with the car OFF.......
You should never see 13 volts, except for a few seconds right after the charging stops.

A healthy new battery might read 12.5 or so while some of the computer boards are still "alive"
and then should rebound to about 12.8 when all (or most) or the current flow actually stops.

 

Where are you getting your batteries, and what brand?

How much driving are you doing, say per week?

 

have no idea what you said...

 

?

 

Have no idea WHO you are talking TO.