Time for a new battery or no?

[m3fan]

I had my car in the "on" position (2005 LC, w/Nav) for probably 40 minutes while trying to get Techstream to connect correctly (completely separate mess/discussion). This was enough to totally kill the battery. The battery has a 1/12 sticker on it so it's coming up on 4 years old.

Is that much time in the "on" position enough to really kill a strong battery? The battery was taken to below 11.5V FWIW. I just had it on a 10A charge for about 2 hours and it almost cranked over but is still below 12V after that attempt. With winter settling in I'd rather buy a new battery if this one is at all on the weak side.

 

[Nolan Sylvester]

I'd take it and have it tested. Most machines can test alternator too but I'd say replace it. I just hate being stranded

 

[Sandroad]

For sure get a new battery. Symptoms are of battery failing. New battery and clean connections should fix you right up.

 

[phippsj]

Pay it now, or pay a lot more later. I never mess around with a suspicious battery.

 

[m3fan]

I purchased the "Solar" load testing gadget mentioned and tested at the end of this video so I'll throw it on there and see just to double check. I figure having 5 vehicles and a lawn mower I should probably own this thing, and it was under 50 bucks on Amazon.

 

[bucfl]

Probably a bad cell. Get it tested. The OEM batteries are great and cheap compared to auto store brands.

If I remember it was $85 for 5 year or $109 for 7 year warranty.

 

[hoser]

Solar battery tester is a cool little gadget. I've using it for some time and recommend it for those who have lots of batteries to maintain/monitor.