ZeroPhone hardware debugging
Verifying that protection circuit works (in general)
This doesn't say anything about whether the protection circuit works reliably, only whether it functions at all. However, it's a good first step to start with if you experience power issues.
- Make sure the battery is not too low, if the battery voltage will go lower than 2.5V, the protection circuit's low voltage cutoff should trigger.
- Shut down your ZeroPhone, unplug both battery and MicroUSB charging cable from it
- Plug in the battery, then plug in the charging cable, wait for 2 seconds and unplug the charging cable
- The OUT+ and OUT- terminals now should be energized and should have the battery voltage across them.
- If you have the SD card with a vaild image inserted, holding the white button near the battery connector (on the backside of the back board) should power up the Pi Zero - the green LED will light up, indicating the boot process.