Frederix

Apologies, I was completely wrong in my post yesterday! Autopilot can engage with NAV 2 when using the 530. The button on the autopilot marked NAV 1/NAV 2 does flip the AP source between the two, it just doesn't illuminate NAV 2 (at least on Xbox) so it looks like it hasn't changed. Sorry for misleading you on that!

As Ark said you use the the keyboard panel marked RNAV/NAV2 to tune Nav 2, and enter the course. This displays on the CDI on the left. I spent a lot of time trying to work out if you could use Nav 2 as the source for the Autopilot, but unless I'm missing something, you can't. There's a button on the autopilot panel marked NAV1/NAV 2 (when using 530), but that just flips from vor/loc to gps mode. To add to the confusion it doesn't change the CDI annunciation on the 530 (though it's functionally doing the same thing). So Nav 2 works fine, but only as guidance, not for AP. Same for the 750.