APM 2.5.2 isn't outputting a signal to servos


I'm having trouble with my new APM board. I have it all working and set up with Mission Planner. I can see the transmitter signals being received in mission planner but when in manual mode the one servo I have attached to the output rail isn't doing a thing.


I have the JP1 jumper in place and when putting a multimeter across the +ve -ve I see a ~5v signal.


I have tried the servo on other outputs but see no movement there either.


When testing the APM with X Plane I see no outputs to the simulator either.


Can anyone help me out? I've uploaded a video that might explain things a little more clearly.



With the aid of a multimeter I have figured out the issue. There is a problem on the board that is causing the voltage to drop to 3.8 volts on the output rail with the JP1 jumper attached regardless of input power source. When I measure the resistance from the positive input to output channel one pins with JP1 in place it is a lot higher that I would expect.

If I remove the JP1 jumper and power the output separately things work without issue. So it looks like a manufacturing issue. I am returning the board for replacement on Monday.

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  • Admin


    How are you powering the APM? Are you using a PM or what?

    What firmware version do you have loaded on the APM?

    What other components do you have attached to the APM? GPS, compass?


    TCIII ArduRover2 Developer

  • Moderator

    Mark, can you post a picture of where you're plugging in the servo, can't see clearly on the video?

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Aug 31
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