Not charging from solar if battery is below about 3.85v

Firmware
3

I admit that I don't fully understand the implementation of this command (especially for E-Series), but maybe it's causing your problems?

.batteryChargeVoltage(4110) isn't one of the options either.
I think you want (4112) or (4208) for the termination Voltage.

You might want to Reset any previous "Sticky" PMIC calls as @lanceseidman suggested, and then only these 2 settings for a Panel test:

    .powerSourceMinVoltage(5080)  //assuming a 6V Panel
    .batteryChargeVoltage(4208)  // or (4112)