HTCC-AB02S RGB flashing when temperature is below zero

In my GPS tracker program for the AB02S I wanted to use the RGB led for my own purposes, so I set
LoraWan_RGB=0 and manually configured the led to glow red for error conditions.

All this worked perfectly, but when I took it outside on a cold day to test the tracking, the RGB led started flashing unexpectedly.

It seems to flash when Lora radio communication is happening.

This isn’t a problem for me as the finished device won’t get cold, but I thought you might want to know about this.

To reproduce this I put it in my freezer (in a plastic bag)


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Seem the LED and Lora draw too much current and the Li-ion battery cannot provide such a current at low temperature.

Did you power the unit by battery? If yes, please check battery voltage or 3.3V at low temperature.
Powering the unit using an external DC power supply.
Reduce the brightness of the WS2812 LED from 100% to 10~25%


Yes, it was running on battery power, I added a display of the voltage to the OLED and the voltage is low (3V) when this happens.

Thanks for the info.