Linux.Is.Skynet wrote:...before I charged it the last time I drained the battery running in diagnostic mode (Running brushes, vacuum and drive wheels) for two hours. Maybe there's something screwy with it's mobo. ...
There is no evidence that this is a mobo fault; however, I can point to a faulty Roomba operator as being a major threat to the hardware!
This is a perfect example supporting iRobot's policy to not honor a valid warranty after determining the operator had run the robot's factory tests!
You, L.I.S., have ignored the user warning given in the test procedure, where it says:
Test-Proc wrote:...a Roomba in Diagnostics Mode is operating without the normal safety features that stop the motors when Disco is either lifted off the floor, or a stout article becomes wedged in a running mechanism. Not only must due care be exercised when using hands to reorient Roomba while its motors are powered, but if anything halts a running motor, for more than a second or two, there is great probability that the motor or its related electro-mechanical parts could be ruined! ...
...and, specifically the phrase "operating without the normal safety features" is the critical portion. I will grant you that the warning's wording stresses operator safety, and mechanisms' safety (including their electronic drivers' safety), and says nothing about battery safety. So that warning is weak in that it is not idiot proof.
By operating Roomba for two hours (possibly locked in Test-12) it is highly likely that you drained so much charge from the battery that its terminal voltage fell far below the 12-volts that Roomba will ordinarily halt a mission. If your Roomba stopped with it Power button lit RED, then Roomba's low-voltage sensor was still operational (and the battery had a safe load shut-off), however, if it stopped with all LEDs dark it is likely that battery voltage fell below five volts (expected to be a battery-killer)!
Once the load had been removed from it, the battery voltage may have climbed a few volts as chemical equilibrium was restored, and the influence of internal-resistance removed. Assuming a no-load terminal voltage of 8Vdc, the mean cell voltage would have been on the order of 8/12 = <0.7V>. But, if one or more weak cells are in the pack, they could have shown voltages near zero level. This guesswork is merely saying: You may have ruined that battery. If not that, then you shortened whatever life it may have had remaining.
OTOH, that battery was already under suspicion as being a contributor to your Roomba's fault symptoms. I'm a little surprised that it ran Roomba (in T-12) for as long as it did. Two features may have assisted that longer than expected run-time: 1) (primary) Wheel motors were using much reduced power -- compared to normal mission speed, and 2) (minimal) Additional charge was drawn out of the battery by blowing past the normal 12-volt limit.
IMHO, further troubleshooting of your system should be preceded by confirmation that you have a battery capable of operating Roomba in clean mode. That can be accomplished by load testing the (apparently) charged battery. If interested, do an "Advanced search" using this query string "+battery +load +test", then search those results for "lamp", and visually scan through the twenty-some posts to get an idea of what battery load-testing involves.