help: Garmin GI275 heading now reversed?

alanbreck

Pre-Flight
Joined
May 15, 2015
Messages
78
Display Name

Display name:
AlanB
Anyone seen this problem?...

I have a pair of GI275 s in the middle of my 6 pack, and a GNX375 in my avionics stack.

Everything seemed to work fine before. Then the plane was in the shop for a couple months for annual. And now, the GI275 heading is reversed (i.e. if I fly 360 heading, it shows 180), and the airplane icon on my GNX375 is pointing backwards.

The shop says they didn't do anything to the instruments/avionics during annual ... they mainly just did the overall inspection, and replaced a few things FWF.

Is there a compass recalibration feature on the 275? Or is there a remote-mount compass which may be the problem? (if there's a remote-mount compass, I'll have to try to figure out where that is on this plane ... not sure)

To add to the mystery ... on one of my recent flights, as I was looking at the 275, at that very moment I saw the heading indication flip 180 to the proper heading. And the icon on the 375 flipped to match, as well. And then about 10 seconds later, everything flipped back to being reversed. I've only noticed this happening once, so far.
 
I don't know if the GI275 uses a GMU11 magnetometer, but if it does, then it could have been reversed in orientation (especially if it was on an inspection panel), or the GI275 somehow reversed what it is expecting on the orientation. I know this is what would happen on a G5, but not sure on the 275. I would assume they use the GMU11 for that, so that's where I would start.
 
I don't know if the GI275 uses a GMU11 magnetometer, but if it does, then it could have been reversed in orientation (especially if it was on an inspection panel)
That was my first thought as well.
 
Back
Top