How do I test 12 volt auxillary battery?

I've research and see how the ones with nav can do it but is there a method for us non-nav peeps. I left a reading light on for a couple days so the car wouldn't start. I put a trickle charger 1.5a on it overnight and it seemed even worse the next day. Then I took my motorcycle battery out placed it in the trunk and using car jumper cables was able to start the car. I drove it around then was able to turn it off and successfully turn it on but that was just right after. I let it run some more and put back on the trickle charger. When I turned it off I used my voltage meter and it showed 12.7 volts at the terminals but I think it's supposed to be just above 13 volts. I've read to remove it and take it to pep boys for a load test. I've read to hit the lock button to turn off the car so it draws less power.

 

I'll check it later tonight and see. On a side note I have no idea if it's the original 2010 battery. Maybe if I take it out I can see a date on it somewhere. If it's original maybe it's a good excuse to get a new one since they probably don't last past 8 years so much.

 

Thanks Wil, but I think this method is for the ones with Nav right? I don't have nav =(.

 

Oh ok yeah I had a gen 2 before and they had a nice color display. The gen 3 doesn't =(. I probably need to change it anyways since it's probably old and I'm playing with fire(but really electricity =P)

 

Update,
So far so good. I check the battery and it was 12.7 volts when car off and has been starting for a few days. The only thing I noticed is when I push the start button it seemed to activate the car, all the dash lights light up but the engine didn't do anything, then I hit the start button again and it started. It seemed like it went into the mode when you press start twice without having your foot on the brake. It did that 2 times so far. I'll google and see if that is in indication of the battery dying.

 

I noticed it did it repeatedly now. I've had to hit the start button twice while holding on the brake numerous times now while pushing hard. That sounds like it could be the culprit. I'll check to see if the brake light comes on with light pressure but if it does then that would eliminate the break light switch right? It has only ever done it now that I killed and recharged my 12v battery.

 

Looks like at least one other person had the exact same issue. I did check the brake pedal switch and it's fine from looking at the brake light come on. I check the voltage of the 12v battery and it's 11.8v so I bet it drops even lower the longer it sits. Ironically it started just fine when I went to check by pressing the start button. Sounds like it's just the battery.

New Prius peculiar start-up problem | PriusChat

 

Sorry I should clarify. 100% of the time when I hit the star button the engine will come on within seconds and never has it not come on so not sure if that's another issue. Pretty sure it's normal for it to at least warm up a sitting engine. Also when you depress the pedal the engine should come on. The shift knob should allow the D or R to engage which it didn't also. I supposed if you just parked a warm engine then restart it then it won't necessarily come on but from a parked situation I've always had it come on. Bisco was right and I'm sure it's the 12v battery especially now that I see it's below 12v =(. Time for a new battery

 

Yes your'e right. I was just thinking we all have prius(es) so figured we all know pressing start isn't an immediate start if at all till we start to drive away sometimes. I'm sure some peeps still don't realize that but hopefully everyone here does.

 

I didn't see one but I didn't remove the battery to get a better look at the other side or the top.

Edit: I googled and found this thread
12V battery date code | PriusChat