MightyBoost in Standalone mode

[andromeda]

Hi,
I have a MightyBoost and I have solder the pins to get it in Standalone mode.
I have connected to it a 3.7 lipo battery 3800mah to the proper connector.
Now if I connect a Rpi3/Rpi2 to the UsbA connector nothing happen.
If I connect power to the micro Usb of the MightyBoost the Rpi boot correctly.
What I will expect is that connecting battery + Rpi the Rpi boot normally, then if I connect the
micro Usb the Rpi continue to run and then the most important if I disconnect the micro Usb the Rpi
continue to run on battery without booting (as an outage will happen).
What I don't have understand or I have to do obtain it ?
Thanks in advance.

[Felix]

Sounds like you're doing it right but can you post some photos of your wiring and the board jumpers please? (top/bottom)

[andromeda]

Hi,
here some photos...

The last one Batt_and_Rpi_and_Power.jpg have lights both ON. Rpi and MightyBoost.

Thanks in advance

[Felix]

Here's your problem:

[andromeda]

Yes,
that's the problem.

Thanks