During my past 3 or 4 flights I've noticed a strange behavior regarding the receiving of the ILS signal. I generally tune the ILS freq. and course before the top of descent. Lately I've noticed that as I approach the runway I have no indication of localizer or glideslope when I am definately in range. The funny thing is, if I press the app button on the mcp, suddenly the magenta localizer and glideslope indicators appear and the ac starts tracking. Strange.

NAV frequencies are definitely active? Top left of PFD, does it show anything?

Is glideslope selected ON in the FMC?

NAV frequencies are definitely active? Top left of PFD, does it show anything?

Nav freqs are active...can't remember if it was showing on PFD..

Is glideslope selected ON in the FMC?

That's an option?

At some airports you wont get the signal until in closer, but if you dont see them by around 20 miles out, then there is a problem. Usually the biggest issue in the Navgraph data, it uses current freqs and FS doesnt, so if its been changed you need to enter the FS one not Navgraph

At some airports you wont get the signal until in closer, but if you dont see them by around 20 miles out, then there is a problem. Usually the biggest issue in the Navgraph data, it uses current freqs and FS doesnt, so if its been changed you need to enter the FS one not Navgraph

i've got the correct freqs dialed in...The strange part is that the localizer and glide slope don't come alive until I hit the Nav button...

i've got the correct freqs dialed in...The strange part is that the localizer and glide slope don't come alive until I hit the Nav button...

Could you post a screenshot of just after you press the APP button and get the LOC/SLOPE?

At some airports you wont get the signal until in closer, but if you dont see them by around 20 miles out, then there is a problem. Usually the biggest issue in the Navgraph data, it uses current freqs and FS doesnt, so if its been changed you need to enter the FS one not Navgraph

Exactly.That's why, before each flight I do, I open the map and find the airport that I'm flying to and then copy all the ILS frequencies onto Notepad. It's really handy.

During my past 3 or 4 flights I've noticed a strange behavior regarding the receiving of the ILS signal. I generally tune the ILS freq. and course before the top of descent. Lately I've noticed that as I approach the runway I have no indication of localizer or glideslope when I am definately in range. The funny thing is, if I press the app button on the mcp, suddenly the magenta localizer and glideslope indicators appear and the ac starts tracking. Strange.

I have exactly the same strange behavior when approaching ENVA RWY 27 ILS. No localizer or glideslope indication when in range but when hitting APP the magenta localizer and glideslope indicators appear. (PMDG 737 -600) I have not tried the same approach with 737-800/900 NGX. gura75

Is glideslope selected ON in the FMC?

Does this need te be on for the ILS signal to be picked up and shown?Bert Van Bulck

I'll bet almost anything that when you push the APP button what you're actually in is FAC and G/P, the IAN modes, not VOR/LOC and G/S. The ILS freq probably is different from what's in the navdata - typical FSX vs. current real world date issue. If you have no valid ILS signal and press APP, it'll go to the IAN modes.

I'll bet almost anything that when you push the APP button what you're actually in is FAC and G/P, the IAN modes, not VOR/LOC and G/S. The ILS freq probably is different from what's in the navdata - typical FSX vs. current real world date issue. If you have no valid ILS signal and press APP, it'll go to the IAN modes.

Interesting. Thanks Ryan, I'll look into that. I've noticed that it only happens occasionally. I'll bet you're right too!!