I bought a Hexa B with APM2.5 here in Germany. After installing the firmware I could not connect via MAVLink, it stopped when recieving the parameters. It was possible to connect via terminal but all setup or test functions for the sensors failed. Reading the forums, i figured it was due to the 3.3V chip, so I returned it and got a new one. The new one connected fine, I could set up everything, sensors were fine, and I was starting to finetune everything. Yesterday I tuned the PID setting, holding the copter in my hand in my appartement, powering it up with no problems at all. Today when I went to the field to fly it, the ABC LEDs weren't on and I couldnt arm it. So I went home, tried to connect, but it timed out. After installing the Firmware again, MAVLink stopped when recieving parameters, so i connected via Terminal and had the same Problems as before. Dataflash, Magnetometers and Gyros are not working, so it seems it's the 3.3V chip again. Does anyone know what's causing this? is it an inferior part or could there be something wrong with my power module?
please help me, I just don't want to bother my vendor again and again with this.