KSFO ILS 28R full procedure (course reversal at DUMBA), chart:http://204.108.4.16/d-tpp/1108/00375IL28R.PDF It flies the hold pretty well... doing 180 kts. So I exit the hold inbound, and change to app mode on my mfd. Low and behold, no ILS needles... hmmm... 1) I've got both freqs set (pilot and fo radio)2) both courses set3) HGS elevation and length set4) both FD's on. Obviously the FMA is telling me something's not right. But why? Look at the MCP, no VNAV/LNAV, no APP mode set. I tried to select VOR/LOC when turning inbound from dumba, but that didn't do anything. So then I just selected APP. The light was on for a few seconds, then off. The plane clearly flew the ILS, but I think the source was somehow from the FMS. (Yes it's true I loaded the approach into the FMS, but the source should have been NAV1). What did I miss?

Going by the FAC, G/P, and FMS on the PFD you're in IAN mode. Of course I'm not sure how or why you ended up there rather than on the ILS. I wonder if you were too far away from the airport to receive the loc and GS from the ILS. If that was the case, I'm think you'd end up in IAN mode when pressing APP, so that might explain things. Might have to go fly it myself and see what happens.Of course I could just be completely nuts. :(

You're just nuts! lol... it's possible i was too far away...dumba is pretty far out but I believe you need the ILS course to enter the hold.

Well I just blew my own theory out of the water. I was able to get VOR/LOC and GS to arm even out past DUMBA, so I dunno what's going on. On second thought, which approach did you select in the FMC? Did you pick the ILS, or did you pick an RNAV approach by chance? I'm wondering if you can get IAN by selecting an RNAV approach instead.

Ryan, I did a little more testing on this and the only way I could get it into IAN mode like in your picture is to arm approach mode before setting up the NAV radios for the ILS. I did have a few things different, namely I had the loc/gs indicators on the CPT side ND, and I also had a distance reported in the DME portion of the ND. So that leads me to ask the obvious question, any chance you didn't have the NAV radios tuned prior to pressing APP?