Location of GMU44 & GRS77 in a 2011 DA40-XLS
Moderators: Rick, Lance Murray
- HPNAviator
- 3 Diamonds Member
- Posts: 147
- Joined: Sun Nov 06, 2011 3:16 pm
- First Name: Stephen
- Aircraft Type: DA40
- Airports: KHPN
- Has thanked: 3 times
- Been thanked: 5 times
Location of GMU44 & GRS77 in a 2011 DA40-XLS
Having intermittent issues with loosing heading indication on G1000. Was wondering if anybody on this board knows the location of the GMU44 Magnetometer and the GRS 77 AHRS on a 2011 DA40-XLS. Taking plane to a Garmin 1000 Avionics shop on Wednesday but they have little experience with DA40's mostly Cessna's and Cirrus's. Thank you in advance.
-
- 5 Diamonds Member
- Posts: 2043
- Joined: Fri Oct 15, 2010 11:00 pm
- First Name: Antoine
- Aircraft Type: OTHER
- Aircraft Registration: N121AG
- Airports: LSGG
- Has thanked: 87 times
- Been thanked: 220 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
The magnetometer is located in the wing. check AMM for details. It is available here
http://support.diamond-air.at/da40-180_ ... 73ab0.html
I had a case of losing heading (in IMC just after take-off mind you!) on a very humid and rainy day (yes, in the UK)
To fix it "we" tried two things:
- recalibrate magnetometer (have a G1000 specialist do that!) - was Garmin's recommendation
- check all cabling connectors from magnetometer to G1000 and clean them with the magical contact cleaner (forgot name) that was PIREPed on this forum. It was sold by a an audio recording studio in NY.
number 2 worked. There are quite a few connectors including one which is impossible to reach in he wing root IIRC.
Good luck! Please share the solution as it seems to be quite a common problem.
http://support.diamond-air.at/da40-180_ ... 73ab0.html
I had a case of losing heading (in IMC just after take-off mind you!) on a very humid and rainy day (yes, in the UK)
To fix it "we" tried two things:
- recalibrate magnetometer (have a G1000 specialist do that!) - was Garmin's recommendation
- check all cabling connectors from magnetometer to G1000 and clean them with the magical contact cleaner (forgot name) that was PIREPed on this forum. It was sold by a an audio recording studio in NY.
number 2 worked. There are quite a few connectors including one which is impossible to reach in he wing root IIRC.
Good luck! Please share the solution as it seems to be quite a common problem.
- ThomasD
- 3 Diamonds Member
- Posts: 166
- Joined: Thu Jan 20, 2011 9:53 pm
- First Name: ThomasD
- Aircraft Type: DA40
- Aircraft Registration: N215DS
- Airports: EGGD
- Has thanked: 1 time
- Been thanked: 16 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
The GMU is way out in the right wing - look underneath for a round plate. I had exactly this issue - took ages to diagnose as intermittent.
Went to 3 avionics shops plus Diamond Canada themselves. Spent ages doing recalibrations, balancing the prop, replacing LRUs... Turned out to be a very simple thing - poorly crimped connectors between the GMU and AHRS: the right avionics shop diagnosed it within an hour. FYI there are 4 (more?) connectors between the AHRS and GMU (presumably to make installing wiring easier). The avionics shop who found the problem disconnected the GMU and AHRS then buzzed out the wiring between, gently pulling on the wires.
Suggest you get the avionics shop to do this first.
Also have a look at the AUX page on the G1000 - will tell you if the GMU only or the AHRS also has a problem.
Good luck.
Went to 3 avionics shops plus Diamond Canada themselves. Spent ages doing recalibrations, balancing the prop, replacing LRUs... Turned out to be a very simple thing - poorly crimped connectors between the GMU and AHRS: the right avionics shop diagnosed it within an hour. FYI there are 4 (more?) connectors between the AHRS and GMU (presumably to make installing wiring easier). The avionics shop who found the problem disconnected the GMU and AHRS then buzzed out the wiring between, gently pulling on the wires.
Suggest you get the avionics shop to do this first.
Also have a look at the AUX page on the G1000 - will tell you if the GMU only or the AHRS also has a problem.
Good luck.
- HPNAviator
- 3 Diamonds Member
- Posts: 147
- Joined: Sun Nov 06, 2011 3:16 pm
- First Name: Stephen
- Aircraft Type: DA40
- Airports: KHPN
- Has thanked: 3 times
- Been thanked: 5 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
Thomas and Antoine, thank you for your replies. Do either of you know where the AHRS is located? I did check the AUX page and no errors show when the heading indication is lost. I wonder if there are any error logs in maintenance mode on the G1000 that can be accessed to see what has happened. Also one other question do you start your engine while the AHRS is still aligning or wait until the AI and heading come up before starting the engine?
-
- 5 Diamonds Member
- Posts: 2043
- Joined: Fri Oct 15, 2010 11:00 pm
- First Name: Antoine
- Aircraft Type: OTHER
- Aircraft Registration: N121AG
- Airports: LSGG
- Has thanked: 87 times
- Been thanked: 220 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
Hi IIRC the AHRS is mounted near the avionics rack, under the baggage compartment.
Check this for more background
http://www.pprune.org/private-flying/37 ... blems.html
Check this for more background
http://www.pprune.org/private-flying/37 ... blems.html
- ThomasD
- 3 Diamonds Member
- Posts: 166
- Joined: Thu Jan 20, 2011 9:53 pm
- First Name: ThomasD
- Aircraft Type: DA40
- Aircraft Registration: N215DS
- Airports: EGGD
- Has thanked: 1 time
- Been thanked: 16 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
Actually I am thinking again and will check - I seem to remember that maybe I had the same i.e. no red X when it was just the GMU connection problem - I have some photos of the G1000 screens from the time concerned, I will find them this evening or tomorrow and see. From recollection the GMU does not have a direct connection to the G1000 - it has 4 wires that only go to the AHRS - so from memory I am not sure that it has it's own line on the G1000 AUX page (and if this is the case there could be a connection problem between the GMU and AHRS which is not shown).
BUT - health warning - I might be completely mis-remembering - I will check and I'll get back on this
BUT - health warning - I might be completely mis-remembering - I will check and I'll get back on this
- ThomasD
- 3 Diamonds Member
- Posts: 166
- Joined: Thu Jan 20, 2011 9:53 pm
- First Name: ThomasD
- Aircraft Type: DA40
- Aircraft Registration: N215DS
- Airports: EGGD
- Has thanked: 1 time
- Been thanked: 16 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
My mistake ! The GMU does have an indicator on the AUX page - you need to scroll down on the AUX page to see it.
Photos attached showing the red X by the GMU and the HDG with red X
Photos attached showing the red X by the GMU and the HDG with red X
- Sandy
- 4 Diamonds Member
- Posts: 247
- Joined: Mon Apr 04, 2016 12:30 pm
- First Name: Sanford
- Aircraft Type: DA40
- Aircraft Registration: N159PS
- Airports: KPDK
- Has thanked: 11 times
- Been thanked: 48 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
I have had intermittent issues with the heading taking a long time to come up. Each time it would be X'd, as in ThomasD's first photo. Unfortunately, I never looked at the Aux screen when it happened. Last week I had a new issue, in that the heading came up, but I had a red X to the right of the Altitude tape. Again, I forgot about checking the Aux screen, but the heading was working perfectly. After thinking about the issue, I went back to my hangar, and, sure enough, I had the red X, again. This time I went to the Aux screen (engine off in the hangar), and saw that there was a red X on GMU1. Related to the heading X issue? Other thoughts? What does the red X on the PFD indicate? Why was heading working perfectly (on ground and in the air) with the red X on the right of the Altitude tape?
- CFIDave
- 5 Diamonds Member
- Posts: 2682
- Joined: Wed Nov 07, 2012 3:40 pm
- First Name: Dave
- Aircraft Type: OTHER
- Aircraft Registration: N333GX
- Airports: KJYO Leesburg VA
- Has thanked: 234 times
- Been thanked: 1480 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
FWIW, I've seen the big red X in the PFD precisely where it is on your display -- it was caused by a database mismatch. This was in a DA40 by not having the same NavData file loaded on both PFD and MFD.
This would be a good thing to check first.
This would be a good thing to check first.
Epic Aircraft E1000 GX
Former DA40XLS, DA42-VI, and DA62 owner
ATP, CFI, CFI-I, MEI
Former DA40XLS, DA42-VI, and DA62 owner
ATP, CFI, CFI-I, MEI
- Rick
- 5 Diamonds Member
- Posts: 1575
- Joined: Tue Jul 06, 2010 10:09 pm
- First Name: Rick
- Aircraft Type: DA40
- Aircraft Registration: NONE
- Airports: KROA
- Has thanked: 107 times
- Been thanked: 297 times
Re: Location of GMU44 & GRS77 in a 2011 DA40-XLS
Was anything listed under the ALERT (or ADVISORY) button on the far right of the PFD? It looks like it is lit up in your picture, indicating there is some message there that might shed some light on the problem.
Roanoke, VA (KROA)