Garmin GFC507 AP Failure today

[Trooper11040]

Completely lost my AP (red X as well just not shown in photo) in and out of IMC…not sure what happened. My avionics shop had me go into the config, and servos were both online. The only thing grayed out was the GFC507. It was an extremely uncomfortable flight with todays OAT…I’m wondering if the unit just got too hot?

 

[Richard Connell]

So could you use the AP via the touchscreen?

My AP intermittently was cutting out earlier in the year similar you what you describe and I ended up with the new servos (just before the program to replace them was announced). Has been fine since. Limited information from Garmin as to whether it was the issue or not, they just looked at the file and said new servos all round…

WRT the heat, I suspect most of the hardware can cope with the typical heat scenarios encountered in service although if the GMC is up on the glareshield I can see that getting very hot in an parked aircraft. I still doubt hot enough to kill it tho.
In my RV7 in summer my old GNS430s bezel would get too hot to touch in summer in flight.
I have noticed once in the peak of summer I got into the plane on a 40+c day after it had been parked all afternoon and the GDU was dim at startup. Never seen it again but I assumed at the time it was some sort of heat related protection. I didn’t fly so can’t confirm if it would have resolved. It was fine the next morning.
I think you have a servo failure.

 

[mburch]

Your GDU display records diagnostic information about abnormal autopilot disengage events, which can be accessed via the Tools item under the main menu. If you have a data log on your SD card for the flight, that will contain additional data. In either case, you can send this information to [email protected] for analysis.

The GMC 507 is not required for operation of the autopilot unless you have flight control monitors enabled. I would check this configuration setting if there is any doubt.

If the illuminated labels on GMC 507 light up when power is applied, but the unit does not communicate, a wiring issue is the most likely explanation.

Appendix D of the G3X installation manual lists the environmental specifications for the various components. The maximum operating temperature of the GMC 507 is listed as +55ºC.

 

[rv8ch]

Do you have a way to powercycle/reboot the servos? I sometimes need to do this on my GRT servos, which are of course not the same as the Garmin servos, but they are both little computers.