Lowest functional battery voltage?

[mitchx3]

Backstory: Alternator died ~15mi from home. Shut my lights, blower, radio off and watched my battery voltage slowly drop from 11.8 to 11.3 as I drove home. Kept RPMs up in hopes that some small amount of charging was happening (I think it was because i'd gain 0.1v from idle to 2k rpm many times) but at the potential cost of more ignition coil current usage. Made it home but raised the question:


What's the lowest voltage you've observed where an explorer continued to function?

 

[410Fortune]

11
Volts flat
My bronco had an optima battery that lost one of its cells
Was at 11.0 flat when it would no longer move
I don’t want to see below 12 ever
Different voltage gauges will give different readings too

 

[Fix4Dirt]

This is one I can talk about... I'd lost the alt in Big Bear (circa 140 miles from home), and was able to limp it home. Made it home at 11.1 running or thereabouts. It still started somehow to move in and out of the garage.
This may have been the problem though not like Jamies dead cell haha. Could never be sure what truly caused it... 11.1 measured on Fluke meter. Funny enough that battery continues to function even after it died from a random parasitic draw that I ne ver found again.

 

[J_C]

I had my alternator die and noticed about 1.5 miles from home, when it wouldn't start due to low battery. It ran fine on a trip to the store, then had to jump start it, didn't yet realize it was alternator instead of battery.

With what little charge the battery had from the jump starting, 1/2 mile down the road, the dash lit up like a Christmas tree due to false set trouble codes. Does that count as still continuing to function? I imagine I was also getting misfires as it was rough running, but it kept running so I made it home.

It was around 10V once shut off and sitting a few minutes at home till I got a multimeter, so might have recovered a little bit of voltage compared to under load, driving. This was at night, so I had headlights on as well.

 

[BrooklynBay]

Check the terminals for corrosion which causes a bad connection. Your meter will show a lower reading than the real reading since corrosion creates resistance.