today I went out to test the new 2.1 Arducopter firmware and was surprised, when all 4 ESCs made the motors beep on start-up, (like beep-beep-beep... twice a second) therefore no spinning motors and no flying. :(
I went back home - surprisingly there was everything fine. Motors spinning without any problems. What did I change? Nothing?
Yes - I went inside, where it is warm. Outside we have around 1°C here in Berlin.
So I went back out, motors beeping again. Then I warmed the ESCs with my hand and after around 20 seconds the beeping stopped. I did this one by one and in the end everything was fine.
Is that a known problem? Which components do not like the cold?