APM doesnt boot

Hi, i just bought the APM from HK, but it doesnt work, first time the red and blue leds were flashing, and it was possible to connect it with the mission planner. But today i startet to work on my quadrocopter, so i connectet it to my pc and nothing happened(i never connectet RX and escs to the APM).
The power led is on, but nothing works.
How could i solve that problem?

Greetings David

[color=#00BF00]This is not a Copter software support question, it’s a hardware problem!
For support for Hobby King or other clone products, please contact the respective manufacturer.
Topic closed.
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