No Boot on Battery/ESC or UBEC

I've been testing my purple board through the USB and it works good enough to replace an ArduPilot Mega 1 on an EasyStar.  Everything is connected and the power jumper is in so the ESC is supplying system power.

But, the APM2 will not start up on either ESC or UBEC power.  Even wired in, it still boots on the USB power, as it has always done.  The APM1 never had any problems with power on this plane and another APM1 always works on a T-28.

Has anyone seen this problem with ESC/UBEC power? 

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  • Anything new about this topic ?

    I've sent back my board to 3DR, it came back with a new shield, the dataflash card doesn't seem to move in its slot anymore. We had a successful mission, and on the second one, GPS fix problem appeared again. 3 hours in the field of extensive testing... of course when only connecting the board with USB, fix happens in seconds (like always)... When powered from the ESC's BEC on the output rail same problem with satellite acquisition... The first mission (earlier today) was executed with strictly the same protocol, the bug reappeared after battery change. We also changed our ESC (which after all  was working alright) for a $65 one with integrated 5A S-BEC.

    Conditions were perfect : clear, open sky, no trees of whatsoever around, cell phone on the ground was able to get a lock to 10 sats, APM2 did catch 7 or 8 when plugged to USB (and GPS fix), on the lipo it went up to 5 without getting a fix.

    We've tried everything, with or without XBees, we unplugged everything (current sensor, airspeed sensor, Rx, etc) nothing changed.

  • I have a similar problem with a new APM2

    I have managed to write the firmware and do the initial setup of the APM2 board but when I power down and the power up with just the battery it refuses to start up. I have power coming in on the Output rail and the power is 4.95 VDVC. If I measure the power at the input rail and the analog rail I get 4.68 VDC. I ran a jumper between the input rail and the output rail but same thing.

    This is what I see, hook-up USB to the APM 2 and the unit starts to blink and eventually you get a lock C and a 3DFIX. I do not connect Mission Planner. I have tried the same with a USB battery but nothing. Next I hook up the main battery and turn on the transmitter. I am now able to arm and run the motors I can also disarm the motors. Now I disconnect the USB cord and everything continues to function, arm, run motors, disarm.  Now I disconnect the main battery wait a few second then hook up the main power. Nothing just a blinking 3DFIX and a solid green power indicator.

    I did try removing the SD card and it does seem to boot but when I put it back in it will not boot.

    Any ideas?

  • Developer

    I have the same exact problem.

    APM2 board, every time I boot it stays stuck on blue light, no red light. With a reset, it boots fine. 

    I just got Xbees yesterday. Had not seen this before the Xbees. 

  • I have recently developed a similar problem as well. At first the problem seemed to be that when I had the minimosd board connected the APM2 would hang on boot. Sometimes I would get one blue led, sometimes no leds. I would remove the minimosd and it would work. Lately the boot freeze has been happening more often, even without the minimosd attached. Usually if I power cycle 10-20 times it will boot.

    After reading this thread I have tried removing the dataflash card. So far, every time I boot it without the dataflash in (minimosd or no minimosd) it boots fine. I put it back in, and it won't boot. I suspect my dataflash card because I have other problems with it: sometimes I will come home from a flight and find no telemetry has been collected.

  • nobody can help me ?

  • Hi friends!
    I have a problem with the startup of my AMP2, watch the video below it is a problem similar to

    yours or a problem of BEC / UBEC because my engine only works when I turn my APM2 before

    connecting it to the USB.

    Please help me to fix this problem! I cordially thank



    HI, the problem is still here.

    After a day of configuration I've again the same problem, when I power on the board only Blue LED ON.


    In debug windows It STOP load on: INIT GYRO.


    After that message the board do not output any message. If I Press reset button, the board boot fine and work.

    I've tried:

    Arduplane 2.28 firmware

    Arducopter 2.4.1 firmaware


    Any idea? Defective Board?


  • Well today we've been experiencing some different results... at first we only had the solid blue at start problem... which was not really painful since a reset did the job... today we had another one... the APM2 seems to boot right, blue/red LEDs flashing... then solid orange (calibration) and then nothing... We spend 4 hours on the field this afternoon trying to figure out the pattern... the only conclusion we got was : occurring only with XBees, never in USB. Very weird since we never encountered this problem before...

    Another problem : no GPS fix when connected on Mission Planner with Xbee... this, also has never happened before, and we did everything, CLI setup reset procedure, installing ArduPlane from Planner, through Arduino, etc etc... Incredible behavior, so the mission planner shows the numbers of sats, increasing 7, 8... 9 and still no fix, sometimes it drops down to 5 goes up to 8, etc etc... completely clear open sky. We had the same problem yesterday...

    When plugged to USB fix is found in seconds. We haven't changed anything in the plane, same gear, no modifications, as we're have only been testing the nav. Only the Mission Planner have been updated, but we've tried with previous versions as well (especially a version we've done all our first tests with on another computer, which was working quite good, same problems).

    I'm gonna try your workaround and see if it fixes something, and i'll try to update the bootloader and see what happens. This APM2 is driving us crazy...

    About the cause of the problem, i've noticed that the card is quite loose in the slot, most of the times it says there is no card plugged in, you have to push it a millimeter in... maybe this can be the cause ? Some vibrations causing the card to slightly slide out a bit while flying and saving logs can corrupt something ? No idea...



    After a really fast contact by support, the problem is solved.


    The solution is very simple, the problem are some data in the EPROM.

    Try to boot the APM2 without SDCARD, if it boot fine you have only to wipe the EPROM using the cli with the USB cable.

    So insert your SDCARD and erase the EPROM:

    Open the MP and go to the terminal TAB

    Hit Entern three times

    type: setup

    type: erase


    Power off the APM2 and try it with your ESC.



  • We also have the same problem, power on, blue LED goes solid, press reset and it boots normally. My APM2 is from december i will look to update the bootloader. Nice thing that we can solve this issue. Thanks.

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