MU-2 Marquise v2 - HDG only latches on APU power, drops when APU is removed

[jrsaez82]

Hi everyone,

I’m posting this here in case another user has already seen the same issue and found a workaround before support replies.

I bought the TOGA Simulations MU-2 Marquise v2 for XP12 and I’m having a strange AFCS / HDG / autopilot problem.

I want to be clear that I’m not posting this as a “quick question” without checking first. I have already:

• searched through forum threads
• read the available documentation
• watched videos
• tested different startup sequences
• reinstalled the aircraft
• checked bindings and controls
• and I have already opened a support ticket with X-Aviation

After a lot of testing, this is what I have been able to isolate:

• HDG does not latch on battery power only
• HDG does latch when the aircraft is powered from the APU
• HDG can remain latched with APU on, even after both engines are started and the condition levers are advanced to takeoff
• but the moment I remove APU power, HDG immediately disconnects
• because of that, the AP becomes unreliable or unusable

So at this point it looks less like a normal “how to use the autopilot” problem and more like an AFCS electrical power / bus transfer / plugin initialization issue.

I also found some related threads, but none of them gives me a final answer for this exact behavior.

Has anyone here seen this?

Especially this exact pattern:

battery only = no HDG
APU on = HDG works
APU off = HDG drops

Any hint would be very appreciated.

Thanks a lot.