G1000 GIA1 dropping offline

[dkkim73]

Hi all,

I was on the ground getting ready for a short low IFR flight and saw red "X"s across my COM1 and NAV2 indicators. The system status page showed GIA1, GMU1, GRS1, and GTX1 offline (I think there might have been more on a second page but didn't record it). This resolved with cycling GIA1 and COM1 circuit breakers but came back a minute later and then wouldn't resolve again with several more cycles or dropping both MASTER and ALT switches (all power off except engine + mags).

I aborted the flight and taxied back. Later I opened the avionics bay doors and looked for anything obvious. I couldn't directly see the back and connectors of the GIA1 and GIA2 without a borescope or removing them. Feeling back there blindly didn't reveal any obvious loose connector but I think that doesn't mean much.

A while later in the hangar when powering on, everything came back. But I'm a bit suspicious now.

What to do? What's likely wrong?
I've heard it's helpful to periodically "re-seat" these connectors somehow.
 

Thoughts:
-bad breakers?
-bad connectors?
-bad GIA1? (I would imagine the logs would need to be looked at)

I'm on the ground at KHRF (home). Checked the "kinds of operation" list and I can't launch IFR without 2 GPS receivers even if hand-flying. Also the AP is inop with GIA1 out which isn't ideal. So I'm kind of AOG...lite? ish.  I had been planning to launch Sat to bring home a family member a few hrs away. Maybe it will be VFR. 

We have a local shop that does some avionics but is not a Garmin dealer. There is an avionics shop Aerotronics in Missoula 1 hr north but the real Garmin expertise is in their shop in Billings. I put a Savvy ticket in for additional brainpower. 

Any thoughts appreciated! 

Thanks,

DK

[exM20K]

David, Are you getting a "Data Path Failed" message on the PFD after boot-up?  That is sometimes associated with bad connections.  I forget what the correct contact cleaner is, but garmin should be able to point you in the right direction.  I do recall that it isn't cheap.

 

My #2 GIA failed with this message (along with a roll servo), and o/h exchange unit from Garmin was $3337.00 

-dan

[MatthiasArnold]

One of the most common problems is bad/oxidized contact on the dsub connector pins, in this case most likely GIA1. 
Get a high quality contact cleaner, turn off electrical power, unlock and remove the LRU, inspect all pins (they easily bend), apply small amounts of contact cleaner (remove any supernatant), very carefully reseat the module (do not apply any force, that could bend the small pins), when seated slightly move forwards and backwards sone times (similar effect to repeated reseating).

Do a final inspection and relock the LRU. If you are sure you didn’t bend any pin power up and check all functions. 
This strategy resolved many G1000 issues on my aircraft. 
Sometimes it is not the LRU connector but some other connector on the sensor/actuator side or the firewall through connectors. Examples I encountered :

- oil pressure sensor (sensor connector)

- GMU (AMP connector in the wing, close to the GMU)

- ..

I‘m pretty sure this procedure is applied by many avionics shops before digging deeper  

If your aircraft has TKS (and you utilize it) the probability of electrical contact problems in connectors (and micro witches, e.g inside speed breaks) is even higher.

[dkkim73]

Is this something Garmin support would likely help me do? (find cleaner and advise) Or would they say take it to a shop? 

My regional Garmin expert got back to me with "The first thing I'D try, is rebooting the #1 GIA with a s/w reload, and reconfiguration, as if I'd replaced the unit.  If it STILL was giving me fits, yes-I would most certainly R/R the unit with a another GIA-63W." 

Odd he didn't mention the connector issue. 

@MatthiasArnold From the Left av bay panel , I can see the whole rack. From the Right av bay panel, which is offset aft, I can barely see any of it. So I assume you mean pull the unit out from the "front" (which would be the left side of the airplane) and inspect both sides of the D-sub connectors with the unit out, looking from the Left of the plane.

Do the LRUs release from the front screws only? (there are a lot of screws around the cage). 

Also, there appear to be some RF connections. Do these mate to a pass-through, or do I reach around behind them and unscrew? I'll look for some service instructions, but any tips appreciated. 

TY both for the quick replies! 

 

[dkkim73]

I had a copy of 

G1000 SYSTEM MAINTENANCE MANUAL

STANDARD PISTON/TURBOPROP AIRCRAFT

190-00907-00 September 2008 Revision B

Which includes:

6.4 GIA REPLACEMENT

To remove:

1. Loosen the Phillips screw to unlock unit handle.

2. Pull the GIA lever up towards the top of the unit. This disengages the locking stud with the dogleg slot.

To install:

1. Inspect connector(s) for damaged pins.

2. Gently push unit into the rack to engage the connectors.

3. Push the GIA lever down towards the bottom of the unit, avoiding the use of excessive force.

4. Lock the handle into the GIA body and tighten the Phillips screw.

 

and: 

6.2 GDU REPLACEMENT

To remove:

1. Use a 3/32” hex drive tool to turn each of the four locking sockets 1⁄4 turn counterclockwise until they reach their stops.

2. Disconnect Backshell assembly from unit.

3. Remove and save Terrain SD Card.

To install:

1. Inspect connector(s) for damaged pins.

2. Connect Backshell assembly to unit.

3. Hold unit flush with the instrument panel, ensuring locking stud alignment marks are in the vertical position.

4. Use a 3/32” hex drive tool to turn each of the four locking sockets 1⁄4 turn clockwise (this may require applying a small amount of forward pressure to engage the 1⁄4 turn sockets).

so that makes it sounds like it's just a few screws to access the backside. @exM20K I cannot recall if I got Failed Data Path or not. It sounds as if the GIA side is more likely to have a problem. 

I do use TKS (as if it is going out of style) but have never seen fluid ingress into the area around the rack. It was found in the tail, so I suppose I might be missing some subtle mist. 

If anyone has the spec/link for appropriate contact cleaner, please LMK. Otherwise I will keep looking around...

Thanks! 

 

 

[dkkim73]

Another thought: How often would this be a bad circuit breaker? If it were a static fault I could test for power at the rack I suppose. As an intermittent, harder to do. 

[dkkim73]

Just got off the phone with Garmin. They're loathe to do anything except have me go through the dealer for a G1000 issue. Including download logs. I'll work the phones a bit on that. 

It would seem reasonable to try re-seating the connectors as an end user. 

[dkkim73]

Online LLM-assisted search finds recs for things like Zip-Chem's Sur-Prep 5672/5673 or LPS NoFlash 2.0, as "they are fast-drying, safe on plastics, and have high dielectric strength". Looking at Spruce and other sites, there's quite a landscape. If anyone knows a good Garmin spec, LMK.

 

[Ragsf15e]

9 hours ago, dkkim73 said:

Online LLM-assisted search finds recs for things like Zip-Chem's Sur-Prep 5672/5673 or LPS NoFlash 2.0, as "they are fast-drying, safe on plastics, and have high dielectric strength". Looking at Spruce and other sites, there's quite a landscape. If anyone knows a good Garmin spec, LMK.

 

Not sure what Garmin would say, but Deoxit and LPS1 are popular.

[dkkim73]

Thank you! The local shop had Deoxit so I used that and reseated both. 

Pulled logs first without any real obvious entry. 

Going to keep an eye on it. 

Savvy said the configuration is in the backshell (rings a bell) so I could swap them. Also said SW reinstall might well fix it, if this doesn't. 

Will plan to test tomorrow since no recurrence with several power cycles. 

[dkkim73]

Two long test flights today, no issues at all. 

If it comes back I'll try the swap first and then maybe prioritize getting it to an avionics shop if it looks needed. Hopefully going to annual in a couple months with an avionics expert. 

Really appreciate all the helpful replies! 

[Schllc]

There are also two cannon plugs on the left and right side under the side panels. (I didn’t trace the wires to see what they served)

I didn’t see any signs of water intrusion when I saw the corrosion in mine, so I assume it was condensate from the heating and cooling at altitude changes. 
I was not having any issues, but since they were accessible and corroded, I took the opportunity to take them apart, clean them, and thoroughly coat all with corrosionx. 
there are also large connectors behind the mfd and pfd that are pretty easy to access. 

[dkkim73]

3 hours ago, Schllc said:

There are also two cannon plugs on the left and right side under the side panels. (I didn’t trace the wires to see what they served)

 

Sound like a reasonable target. Are they obvious in terms of their relationship to the GIA's? Ie. in terms of which ones to disassemble and treat? 

3 hours ago, Schllc said:

there are also large connectors behind the mfd and pfd that are pretty easy to access. 

Are these accessible by unlocking the hex screws and just pulling the GDU's forward?

Thank you!

[Schllc]

There are only two that I saw behind the side panels, seats need to be removed and it’s a pretty big job to get to them. Had I not been removing the interior for work I would not have gotten to them. The passenger side is a bit easier, and may be reached with less effort. 
yes to the displays, quarter turn of the Allen wrench and they plug into the back. 

[dkkim73]

So, the original issue has not recurred after cleaning and reseating the GIA's (1 and 2). I briefly tried swapping them but it complained on startup about config, so I moved them back. Someone had suggested with the config in the backshells it would "just work". 

Anyhow, I have been increasing getting a "GIA2 SERVICE - GIA2 needs service. Return for repair." It only occurs some of the time and usually goes away with breaker-cycling for GIA2. Some have suggested a race condition, possible aging of the internal power electronics, etc. It might have occurred once in the past, I am fuzzy on that. But it's definitely changed now. 

Talking to a regional avionics shop he suggested I very carefully re-examine the connectors and the fixation of the backplates. A maneuver being discussed is to go ahead and do the swap. It is not cheap. Re-load of software was discussed but might is about a day of tech labor and might not work if the unit truly is flaking. 

Has anyone here experienced this? 

 

[LANCECASPER]

13 hours ago, dkkim73 said:

So, the original issue has not recurred after cleaning and reseating the GIA's (1 and 2). I briefly tried swapping them but it complained on startup about config, so I moved them back. Someone had suggested with the config in the backshells it would "just work". 

Anyhow, I have been increasing getting a "GIA2 SERVICE - GIA2 needs service. Return for repair." It only occurs some of the time and usually goes away with breaker-cycling for GIA2. Some have suggested a race condition, possible aging of the internal power electronics, etc. It might have occurred once in the past, I am fuzzy on that. But it's definitely changed now. 

Talking to a regional avionics shop he suggested I very carefully re-examine the connectors and the fixation of the backplates. A maneuver being discussed is to go ahead and do the swap. It is not cheap. Re-load of software was discussed but might is about a day of tech labor and might not work if the unit truly is flaking. 

Has anyone here experienced this? 

 

Call Brian Kendrick and ask him about it.

[Fritz1]

David, yes, second Brian Kendrick, he is the G1000 guru, if this has happened in another plane before he has seen it, if this has not happened before he will drill down and get to the bottom of it. -Fritz