Autopilot does not work - M20M - EFS 40 with the KFC150

[Dklossner]

Autopilot won't work:

KFC 15- preflight test is okay:

Sent the KFC 150 and servos to be checked out and they are fine.

The EFS 40 - preflight test is okay:

Getting ready to send it our for bench test but...

When the A/P is engaged the plane slowly climbs to the right. Altitude preslect does not hold.

Has anybody had this porblem and what did they find?

thanks

[jackn]

Most likely it's the AI. KFC150 is an attitude A/P and trys to maintain straight & level(everything else being equal). It must be getting incorrect info from the AI.

[Dklossner]

Thank you, Jack.

My EFS 40 is my AI and it tests okay. Would you recommend that I have it tested outside the plane - or do you have another recommendation. In my area there is not a quality shop.

[jackn]

Obviously, I'm not familiar with the EFS40, but the KFC150 is an analog unit. Your AI looks kinda digital. Maybe the interface? The only avionics shop that I know in your region is at Sporty's in SW Ohio. Good luck

[AndyFromCB]

Call Randy Herren at autopilotcentral.com. Sounds to me like your AI is not sending out proper pitch attitude back to the unit. I was under the impression that EFS 40 was a digital HSI. Does your plane still have the KI256 attitude indicator? That's what probably needs overhaul. $2500 from autopilotcentral.com, few days turn around time.

[Dklossner]

My plane has the King KAS 297B V.S. and preselect. There is no seperate preflight test on this. I believe the instrument is confirmed good within the KFC 150 test.

it also has King KLN 90A IFR Certified GPS/ Slaved to EFIS System.

[wrench]

It's not to far of run in a Mooney but maybe give Mayday Avionics a call first in Grand Rapids, Mi. They do a lot of AP work.