dive and turn when engaging Autopilot

[N38TM]

I'm having an intermittent problem when flying the 300QT.
When go to activate the autopilot after taking off the aircraft dives and turn hard right.
What could cause this?
Flight Directors are on. Altitude set, LNAV engaged.

[Martyn]

Does this only happen with the 300QT variant? Do the flight annunciators indicate that PITCH and LNAV modes are engaged?

[N38TM]

@martyn
I've only noticed it with the 300QT..
Should Pitch and LNAV be engaged before turning on the autopilot?
I was under the impression that you could not engage a mode on the AP unless you
first get the green light indicator that AP was on?
Thanks.

[rustyrdc]

@n38tm no the modes can and should be pre armed. The modes only require the FD to be switched on

[N38TM]

@rustyrdc OK. I try that. Thanks.

[Wildcataa5b]

@rustyrdc thanks for this, I'm having problems with the AP intermittently as well. Maybe the FD is the issue. Something else for me to try.

[rustyrdc]

Take note of what your FD is telling you before engaging autopilot.