I had this issue before, solved it but it’s back again:
I was learning how to do ILS landings and a YouTube video told me that you switch from FMS1 to LOC1 manually, by clicking the NAV button right above the FMA.
However, the plane would just go into ROLL mode and would also refuse to go back to the FMS1 path.
After asking around, I found out that you actually have to hit APPR, instead of NAV, that way the plane will automatically switch from FMS1 to LOC1, due to it’s NAV to NAV functionality, and doing it this way solved the issue, bcz after changing to LOC1 on it’s own, the plane would properly do the ILS.
I did several ILS landings after this, however, today, I was doing one more flight and the same issue returned.
I pressed APPR, waited for the NAV to NAV to automatically change to LOC1, it did, but shortly after it went into ROLL mode again.
I was confused and, since it was a short flight, I just restarted it and did it all again.
Got past the transition vector and this time, just to make sure, I waited for the plane to be completly alligned with the runway, and then I hit APPR.
This time, it went STRAIGHT INTO ROLL, it didn’t even try to do the ILS.
I’ve no idea what is causing such issue.
Here are the flight infos:
06/11/24, approximately 02:15 UTC.
SBKP/15 KONV1A (no STAR) LOMEN ILS P SBGR/10L
LOC/DME: 111.70 IGH (I even downloaded a PDF chart just to confirm that the frequency was correct and yes it was).