Aux Channels/Landing Gear

I can successfully operate landing gear using channels 7 or 8 with the servo lead coming out of the Pixhawk’s Aux1 (servo 9). I can manually deploy and retract the gear and it will automatically deploy when LAND mode is selected, everything works fine. Keeping all the same parameters, but, setting channel 9 in MP to trigger the gear does nothing. Can’t manually deploy or retract the gear nor will they automatically deploy in LAND mode. It’s as if the Aux channels beyond CH8 are inoperative. I’ve read several posts on this issue and understand the parameters that need to be assigned but still can’t get it to work with CH9. Can anyone offer any assistance?

Can anyone offer any suggestions? Has anybody tried using Aux Ch 9-14?

Have you tested the Aux port with a multi meter to ensure it is getting power?

The Aux port works fine if I assign landing gear to Ch 8. However, assigning landing gear to Ch 9 or 10, nothing happens.

Well, I’ve tried everything I can think of. Ch 7 and 8 can both control the landing gear as advertised, but Ch 9 and 10 do nothing when assigned landing gear as an option. In fact, when looking at the sliders in the radio calibration screen, I can only see Ch 1-8 being active, I do not see any activity for Ch 9-14. Surely someone must have some idea of how to resolve this issue?

Hi Will.
I have LG connected to aux ch10. Tried ch 9-11 and all of them are working fine.
I had some adjusting wit PWM´s but i suppose that depend on your LG brand if u need to do any tuning on PWM values.

PX Cube

I’m using the latest Mission Planner 1.3.59. I have SERVO9 FUNCTION set for Landing Gear with min PWM set at 1000 and max PWM set at 2000. If I assign LG function to Ch7 OPT or Ch8 OPT, the landing gear works fine. If I assign LG to Ch9 OPT or Ch10 OPT, nothing happens. I’m stumped.

So you have 14ch radio, all of them assigned to a switches on your remote and still no
PWM´s for ch9-14 in radio cal screen, right ?.
Good luck

I’m using a Turnigy TGY-i10 ch radio. I have assigned a switch to aux channels 6-10. Ch 6, 7 and 8 work with several items assigned, ie: LG, RTL, lost model alarm, etc. When I assign any of these same functions to ch 9 or 10, nothing happens. Also, on the radio calibration screen, I can see the green sliders moving for ch 6, 7 and 8. I do NOT see sliders moving for ch 9 and 10.

Do you see sliders moving for any ch above 8?


I have 10ch radio, all the channels that are assigned to some switch on the radio, same channels sliders are moving in MP radio cal screen allso. (ch 1-10)
Please double check your radio settings, you should have signal thru px if all the channels are mapped correctly on your radio.
Have you tried radio calibration again ?

I’ve tried radio calibration several times and I don’t see the sliders moving for Ch 9 and 10. Other than CH OPTION and SERVO FUNCTION, are you setting any other parameters for Ch 9 and 10?

Common guys, I can’t be the only one experiencing this problem. As I said, landing gear works fine if assigned to Ch 7 or 8 but does not work if assigned to Ch 9 or 10. I can see the sliders moving in the radio calibration screen for Ch 1-8 but nothing for Ch 9 and above. I’m beating my head against the wall. Please, somebody help.

IF you see the sliders in radio cal working for ch 1-8 but not 9 then you have a radio problem.

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I plugged the landing gear directly into Ch 9 of the receiver and it worked, but, I had to switch off PPM mode. Would switching on PPM mode have anything to do with this issue?

Well, after spending a few more days researching this issue, it seems that PPM will only support 8 channels hence why I cannot get Ch 9 and 10 to work. Frankly, I’m surprised nobody on this forum with more experience chimed in to clarify this.

That is your radio not PPM in general.

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