Charge LED pulses when no battery is present

[drmacro]

I am using a clone of the Feather/Huzzah shown in the schematic here:

https://github.com/pantaluna/esp32-mjd- ... ematic.png

When I power the circuit via the usb port and there is no battery connected, the charge led pulses. With a battery connected it is steady bright when a less than charged battery is connected; with a charged battery, the LED is less bright and steady.

At first I thought it might be something with the external 3v circuitry I was powering. So I rigged a separate 3v supply for the external circuitry. This made no change in behavior.

Note: the external circuitry responds correctly to the program that is running, battery or not.

Any ideas on what might be going on?