MGL Avionics User Forum

I have had the Explorer Lite in an aircraft for 320hrs and 5 years now. I initially had trouble with it randomly failing to boot up, and crashing during use. I removed all excess files, maps etc and designed a very basic screen, now boot up seems stable.

It doesn't like being powered on during engine start, despite being told that it is no problem.

My new problem is that the internal AHRS are forever wandering, in bank angle. On initial boot up, it shows a 30 degree bank to the right and then settles to zero after a few seconds. In Flight, it starts off level, but after 10-15 mins it will wander to about 10-15 degrees left or right bank (wings level).

It never used to do this and is quite a distraction sometimes.
I've tried removing the AHRS offset, and recalibrating it. That works initially and then it wanders again.

Engine is a Camit 2200 which runs very smoothly, and panel is soft mounted. Nothing has changed since day one, other than updates etc.

Any ideas?

I saw in the Discovery Lite manual a suggestion to "reset AHRS gyro bias" every year:
https://www.mglavionics.co.za/Docs/iEFI ... manual.pdf

Maintenance items
Every year:
Perform “Zero ASI” procedure.
Perform Gyro bias zero procedure.


Perhaps this might help?

My Explorer Lite AH does something similar. I sent it for service and it did work better for a while but just doesn’t work right. I calibrate it but it has a large pitch error that I can’t completely zero out that seems to cross couple when banked.
The Explorer Lite has a solder mount backup battery inside that failed in about 3 years that effected its stability on start up.

I ended up installing MGL SP-9 AHRS and very happy with how it works with my Discovery Lite.

Good to know

Thanks for the ideas. I've tried everything i can think of (just reset the Gyro Bias again) but I still get the same issue.

Is there a way to check the internal battery without removing the screen?

Wish I could figure out what is wrong with the internal AHRS, not really wanting to purchase external AHRS as it used to work fine (99% of the time anyway!) I may have no choice but to return the screen.