Aspens are disagreeing with each other. Suggestions?

[Oldguy]

Plane is 8 days and 0.5 hours out of the shop. My buddy whose Mooney is at Hawk getting painted took mine to make a quick run to Gulf Shores to get his wife. The photo below is one of the four he took down and back showing this problem. Was constant and not an intermittent anomaly. The PFD is correct but the MFD is off. 
My thought is it has something to do with the indicated wind, as, again, the PFD is correct and the MFD is not. I know this will probably have to go back to the shop - again - but would love to hear someone tell me this is a quick fix and not another week or more to get corrected. 
Anyone have any ideas?

TIA. 

[LANCECASPER]

I’m guessing that the RSM (remote sensor module) on the MFD is defective or maybe just that the “compass swing” needs to be done on that unit.

[Oldguy]

3 hours ago, LANCECASPER said:

I’m guessing that the RSM (remote sensor module) on the MFD is defective or maybe just that the “compass swing” needs to be done on that unit.

I contacted the shop today and they are leaning towards the compass swing as well. We'll see Monday.

Had it back for a week this time. Progress.

[LANCECASPER]

14 hours ago, Oldguy said:

I contacted the shop today and they are leaning towards the compass swing as well. We'll see Monday.

Had it back for a week this time. Progress.

The installation manual calls it RSM Calibration. ( If they still disagree after that you might need to take them to counseling  )

 

aspen installation Manual.pdf

[Warren]

Yes, it is an RSM heading error.  Winds are calculated from TAS, GPS speed and heading.  The GPS Speed and TAS are very close but the heading is off by 50 degrees.

The RSM heading is very magnetically sensitive.  Depending on where it is mounted and how the plane is loaded, you can skew it significantly.  Mine is mounted above the hat rack and on one trip it was consistently off by about 60 degrees from cargo interference.  Removed the cargo and it went back to normal.

Or, it may just need to be calibrated but it is hard to believe that it wasn't calibrated during install.

[RobertGary1]

If you are OCD the MFD is mounted higher than the PFD. Not sure why.

Edited May 27, 2021 by RobertGary1

[Oldguy]

On 5/27/2021 at 9:50 AM, Warren said:

Yes, it is an RSM heading error.  Winds are calculated from TAS, GPS speed and heading.  The GPS Speed and TAS are very close but the heading is off by 50 degrees.

The RSM heading is very magnetically sensitive.  Depending on where it is mounted and how the plane is loaded, you can skew it significantly.  Mine is mounted above the hat rack and on one trip it was consistently off by about 60 degrees from cargo interference.  Removed the cargo and it went back to normal.

Or, it may just need to be calibrated but it is hard to believe that it wasn't calibrated during install.

They did the MFD install and MAX upgrades at the same time but did not move the RSM with the GPS from the PFD to the MFD. When it came back to get corrected, my supposition is they swapped the cables and buttoned it up. Would swapping RSMs between the units make a difference? I would think the answer is a solid yes.

On 5/27/2021 at 11:48 AM, RobertGary1 said:

If you are OCD the MFD is mounted higher than the PFD. Not sure why.

Me neither, and it is another one of the reasons I am strongly considering getting a new panel cut when I do the EDM 900 install. It already looked like a bit of a "Franken-panel" before the MFD install, but now it looks like a listing one!

[David Lloyd]

Me neither, and it is another one of the reasons I am strongly considering getting a new panel cut when I do the EDM 900 install. It already looked like a bit of a "Franken-panel" before the MFD install, but now it looks like a listing one!

In the meanwhile, oblong one of the mounting holes to get them even.

[Warren]

54 minutes ago, Oldguy said:

They did the MFD install and MAX upgrades at the same time but did not move the RSM with the GPS from the PFD to the MFD. When it came back to get corrected, my supposition is they swapped the cables and buttoned it up. Would swapping RSMs between the units make a difference? I would think the answer is a solid yes.

It is likely.  The calibration is specific to the RSM and not the Aspen unit.  Is should be pretty easy to run through the calibration.  You just need an installer or other qualified person to find a compass rose or some other relatively quiet (magnetically) area to go through the calibration.  Enter calibration mode and follow the instructions to taxi in a 360 circle.

[Mooney in Oz]

18 hours ago, Oldguy said:

They did the MFD install and MAX upgrades at the same time but did not move the RSM with the GPS from the PFD to the MFD. When it came back to get corrected, my supposition is they swapped the cables and buttoned it up. Would swapping RSMs between the units make a difference? I would think the answer is a solid yes.

I spoke to my avionics installer about upgrading the legacy Aspen Pro PFD to a Max and installing a 1000 MFD Max. Due to some issues with the Max units, he suggested if I go ahead with either install to include a new RSM for the Aspen Pro Max PFD as the internals have been upgraded for better compatibility with the Max units.

I don't know what issues or upgraded internals he was talking about, but that was his advice.

Maybe @Andy Smith can chime in, if he is around.  

[Oldguy]

To close the loop on this, after a calibration of each RSM with their respective Aspen, everybody in the panel agrees with each other.

Of course, my annual is due this month, I have a week of vacation scheduled to do some diving in Belize, and we just put our house on the market. So in my "spare" time, I will take the plane out and get familiar with flying again. Probably in July.