I’m facing issues intermittently with the Cessna 152 avionics not working as they should, particularly the turn coordinator and the OBS “NAV” light.
The issue occurs during some free flights but not in others. Nothing I do is different between each flight from the start up procedure, to calibrating the OBS to a VOR frequency.
The CDI works as it should and I am able to navigate to the VOR/DME station as intended, but the green “NAV” light doesn’t come on.
Equally, the turn coordinator doesn’t move at all and stays fixed in a wings level position.
Is this a bug or have I knocked a switch during the start up procedure?
How do I fix it?
Any help would be greatly appreciated.
TIA
Below: Cessna 152 banking left over POLE HILL VOR (112.100) - No NAV light showing on OBS. Turn Coordinator fixed at wings level.
That’s generally only for an airplane that has the ability for both radio navigation and gps sources to feed the gauge. When the green nav is lit, it means the CDI is being driven by the VOR radio nav source, basically telling you you’re “green needles” versus following GPS guidance. In this case, the airplane doesn’t have a GPS installed, so that light either doesn’t exist or is inop.
As for the turn coordinator, it’s electrically driven, so check breakers and switches (if those are even functional for that plane - I can’t remember). I can’t really tell by the pic, but is it red warning flag out? If there’s no electrical problem, then I don’t know what’s up.
I don’t quite follow what you mean about the NAV light and GPS.
The NAV light on the OBS in the last picture is the same OBS as the first pictures. It’s just a different flight. Same C152 and same VOR/DME station. When it’s tuned to the 112.1 frequency the NAV usually lights up green when it comes into range of the VOR signal. It does this when the turn coordinator is also functional. However the NAV light and the turn coordinator both being INOP seem to be linked to a common cause. The two issues coinside.
My first thought was that I may have popped a circuit breaker, but they’re not even functional and nothing was popped, so I’m left wondering if this is a bug or if there is something I’m doing wrong.
When starting a free flight from the runway as opposed to parking, and the engine and avionics are already started up, the NAV light shows in green when tuned to 112.1 VOR frequency. The turn coordinator also works as seen below:
Oh, interesting. It’s modeled after a Garmin GI-106A, which has a mode annunciator that indicates whether it is receiving signals from NAV, VOR/LOC, or GPS. NAV is used for when a GPS is installed, but the gauge is n NAV mode, which allows it to interpret and display signals from the NAV radio. You’d be able to switch it to GPS mode using a remotely-mounted button.
If it interfaces with a Garmin 430/530, specifically, it would indicate VOR/LOC or GPS, depending on the similar mode selected on the GPS panel (using the CDI button). I believe it’ll do this for a GTN 650/750 as well.
It’s kind of a mismatched gauge for the 152, IMO, as that particular plane doesn’t have a GPS installed, so the NAV annunciator really isn’t necessary. However, even without a GPS, I think that as long as that unit is powered, NAV should be on all the time and should not be dependent on signal acquisition. The red flags should be the things that tell you whether you’re receiving a station (or more precisely, when you’re not).
But I think you’re right when you say the problem probably stems from the same root. Something is messed up with the electrical system - maybe that component of the systems model didn’t load properly, etc.
edit: you seem to have been able to recreate the problem - nice! I used to fly a plane with a GI-106A, but it was two decades ago so I’m trying recall most of this. IIRC, that nav light was always on as long as the mode was selected - wasn’t dependent on reception.
I’ll log it as a bug and hopefully somebody can look into it. I don’t have any knowledge of these systems and I’m learning as I go along, so when I encounter these kind of issues I never know whether it’s me doing something wrong of the sim.
I’m not home to test anything, but I’m guessing you’re missing turning something on. When you start on the runway, the plane is already set up, when you do cold and dark, you have to do everything, and you’re probably missing something.
Try starting in a parking spot and use the CTRL+E (I think it is) to start the plane and see if the turn coordinator and NAV light work.
If you think they are the same then please contribute there, if not, feel free to create new reports (1 issue per report) filling in the provided template with details information to allow devs/users to replicate/contribute.
@WombiiActual : you mentioned in your post C152 Turn Coordinator (+ADF) Fault - #11 by WombiiActual that the issue with the master battery switch affects the turn coordinator & the ADF. Could it also impact the OBS Nav light reported by OP here or do you think it is a separate issue ?
Did a quick test with the cessna-152-aerobat and seeing the same issue with the turn coordinator. @WildeMulqueen : by any chance do you have the FS2024 version with the Aerobat ?, if yes can you reproduce all the issues with this version too ?
I’ve just tested it from cold and dark. Toggling the battery off and on again works, but it’s hit or miss. You just have to keep toggling until the green “NAV” OBS light comes on and then you know it’s working…. Typical isn’t it.
.