Battery Drain after Coding?
 

During my first attempt at coding, NCSExpert had all kinds of troubles and eventually my battery drained enough to not start the car and threw a bunch of codes. The next day when I had the latest datens finally, I put it on a charger [i know.. like I should have done first] and coded all my mods. After about 30min-1hr on the charger, I started the car and drove for about 45 minutes. I stopped at mcdonalds and 15 min later my car wouldn't start. I got a jump, drove for about an hour. Next morning [yesterday], I put it on the charger for 2 hours. I tried to start the car and no luck. I tried the charger's 75amp 'car start' mode. Still couldn't start the car. I checked right after all this and the battery was 10.46 volts between the terminals. [Today, it was 10.21 volts if that means anything] Is it possible the coding drained it that much? Or does my battery sound damaged?

It sounds like you have a dead cell in the battery.

Dave

It was finally able to get up to 12.5 volts, tried starting, nothing, right back down to 10.5... So new battery it is. Is this something that was just a coincidence? or can it happen any time it gets drained?

Draining a battery down to nothing is a good way to kill it.

Dave