Raspberry Pi foundation did a new version of the Raspberry Pi 2 in last november (Raspberry Pi2 Model Bv1.2 technical document).
They changed the Cortex -A7 processor by a Cortex-A53, so the previous bootloader and the kernel are not compatible. They integrated the new kernel and firmware in the last Raspbian.
As our last image for the Ergo Jr was older than the release of this revision, it was not compatible with this Raspberry Pi 2 revision.
Generation Robots didn’t seen the changing revision, and some Ergo Jr were sold with this non functioning operating system image.
If you have a Raspberry Pi 2 rev 1.2 with the non working image, the green led will blink with a cyclic pattern continuously.
We published today a new version of the Ergo Jr image.
To update your Ergo Jr, you have to download the operating system image (img.zip), and use Etcher to write it to the SD card. More details in the documentation.
It has been tested with both Raspberry Pi 2 and 3 but if you experience issues, please tell us.
It is not directly related, but if you have a previous (and working) image, you can use the update feature of the web interface to update pypot. Among other things, this fix a bug in movement speed feature of the play block in Snap.