No o/p to esc/motors on Pixhawk \board

[attachment=0]2015-02-20 21-17-28 3.bin.log[/attachment]I just upgraded to a pixhawk board. Programmed it with the latest firmware using MP, did all the setup and got the board active. Using MP I can see sats, compass etc, and arm the hex.

Going to failsafe, I see the board arm and motor o/p’s spool up as throttle is increased, BUT, ther is absolutly no o/p from the 8 esc/motor o/p pins. I have checked my taranis is showing below 970 to enable motors, and can see everything is as it should be, but no motor o/p. I erased the board and just downloaded an earlier version to check, but it is the same. I scoped all the o/p’s and no signal is present on any of the 8 0/p’s. I did note the neg rail is on the top row and signal on the bottom row. Has anyone had this problem, or can advise any further checks I can make.
One point, I reformatted the micro sd card fitted with Fat format, but I don’t see that as being associated with this problem. Having read all the posts in the forum, some say format the card in fat32, not sure which is correct, but mine works ok. I also read how to initialise near all logs. i will do that and post if anyone needs them. Have now been able to create a log. I connected, armed and raised thr to around 1400, then held the hex and moved it about various positions. all the time the esc’s are beeping, but no o/p. On startup, all the sounds are correct, but on connecting to MP, I get connecting/done, then the only parameter is pulls down is Terrain, not all the perm that the APM downloads. Also the arm push button just flashes continually with 4 repaeting flashes. It will not go solid.

My guess is you have the ESC’s plugged in wrong on the Pixhawk. They are not the same as APM.


Mike, Don’t think so. Have put a scope on the o/p signal pins and nothing shows. Have also tried the way mentioned in other posts, connect all 3 esc pins 5v, neg, signal, no o/p to motors.

Well the log shows motor out to all 6 ESCs. Also you have it configured as a Plus hex.

So either you are using OPTO ESCs or there is no power to the rail. Other than that the unit is defective.


Yes, I fly my hex as a plus and my esc’s are bec powered, I mentioned in my first post that motor o/p’s are showing in MP failsafe screen and spool up and down as I raise and lower THR. my conclusion was board was half dead, now I’m sure it’s board fully dead (o/psignal o/p wise). Thx for your observations.

as its all outouts, does the ground signal of the outputs have continuity to battery ground?

Yes, on pixhawk and all APM boards the neg rails are all linked together. On mine I also checked signal Gnd is linked to Bat neg.