I was in 2003 Cesnna 172SP today. Like most 172SP's i've experienced, it has bandix/king gps/comm/nav system.
I shot an ILS yesterday using NAV 1 and it was fine. However upon trying to be established on a Localizer using Nav 1(vor) at a different airport, it was not able to detect the needle to final course on a localizer. When I tuned up Nav 2, it was able detect the course and I was able to shoot the approach using Nav 2.

Do you guys know if this is a malfuction with the Reciever #1 or is it something else that I missed?

Yes, I know that there is button you can push to make it switch from NAV/GPS. I tried both setting and NAV1 was still unable to detect the Localizer.
HOWEVER, it had no problem detecting ILS back to my airport.
Vor check was done on ground and it turns out fine.

Could it be Auto pilot?

THanks!~

I don't see how it could be the autopilot. Seeing how you were able to receive the localizer on nav 2, even though you couldn't with nav 1. And this only happened once, with nav one working fine before and after, I'd have to guess that maybe you had the freq wrong on nav 1? Did you identify the station? Are you 110% sure you had the GPS/Nav sw in nav?

Always identify your station as part of the approach setup before starting an approach and if the airplane has a decent audio panel as this one does, maintain a quiet monitoring of the navaid morse code in the background while you fly the approach. This 1) tells you the nav is tuned to the right freq and 2) tells you the nav/ navaid combo is working as you fly the approach. If you had the morse code signal coming from nav 1 and still the flag never drops away from the VOR head, then you know it's the VOR head causing the problem. Usually it's the nav radio being inoperative or tuned to the wrong freq when this happens, so it's hard to know exactly what happened.

Probably wrong freq in Nav 1. If you are sure it was correct, then I'm stumped

I was thinking it would be the wrong frequency as well. Other than that, seemed okay.

Cubdriver, that's a great suggestion, I never thought of that. I'll have to use it on my CFI/I.

This is the recommended procedure when operating on an NDB, since they are prone to atmospheric disturbances, have no flags, and the stations may be unmonitored. I've never used it for a VOR or LOC/ILS though. If you are lucky, the newest avionics ID a navaid themselves and can display it for you.

This is great. I don't like it when I have bleed through on the signal and can hear the morse code the entire time.

USMCFLYR

Yes G1000 was a cool system that I got to put a few hundred hours teaching in!

Song Man,

Have you spoken to the avionics guy at your airport? They tend to know a wee bit more than us mere pilots about this stuff.

Agreed. These navaids are so reliable you generally wouldn't bother. Garmin G1000 shows the station identifier next to navaid frequency to let you know you are getting what you ask for, which is a nice feature.