GSA28 (Garmin Autopilot Servo) fails to update

TimRF79

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Tim
Hello,
I have a certified G3X Touch, with the GFC-500 (Roll/Pitch/PitchTrim).
When putting the newest certified software on teh G3X touch, all items update fine, with the exception of the Roll Servo (even Pitch and Pitch Trim Servo update fine).

The update goes to 100% and then fails, stating “Transfer failed” and “99% Network Error Rate”.

However, the AP worked fine all along (prior to update) and did not have communication errors.

Thoughts?
 
I’d reload the data from FlyGarmin to the SD card and try again.
 
I’d reload the data from FlyGarmin to the SD card and try again.
The other servos updated fine, also the G3X touch is auto pushing the update out.
When I put the SD card in the G3X touch does not offer loading it again.
 
Did you delete and reload the data on the card? I’m just guessing. My exp version didn’t hiccup at all when doing the software upgrade. I have had to reload chart data on the SD and reinstall.
 
Mine are not affected by the SB.
The weird thing is the other 2 GSA28's did update just fine, so i cant be an issue with the software.
 
I don’t know how the servos update. They’re simple motors. The controller is what I’d expect to update. I don’t have a controller. My servos are driven by the GDU.
 
Found this by accident!

Tips:

-If the G3X is having trouble spreading the updates to the remote units like the GSU 25 or one of the servos, then pull the breaker for everything on the CAN Bus so only the GDU PFD1 and that unit are on the CAN Bus. This will clear up the CAN Bus so the software update can transfer easily. Please note that this indicates that there is an issue with the CAN Bus
 
I don’t know how the servos update. They’re simple motors. The controller is what I’d expect to update. I don’t have a controller. My servos are driven by the GDU.
That's not exactly true. The servos are quite a bit smarter than "simple motors". They absolutely have processors, memory and this software.
 
NSS. Did you read the previous post? I’ve never had any servo issues so I’ve never given them much thought.
 
The CAN bus pins are 1-4 from the top left of the connector. I’d give those a look. And if that doesn’t help? Garmin tech support for the G3X is relly good. They’ll sort it.
 
I thought Garmin wanted you to get tech support from a Garmin dealer?

I have local dealer who is a Garmin dealer who installed my panel that I get tech support from.

Last week I started my plane with the avionics switch on, and it created a Ptrim fault. A red ptrim window came up on my G5. Message said ptrim clutch fault. Electric trim quit working and no pitch on my AP. Bummer...

I called my dealer for help and he said we may be able to reset it since it is a clutch fault and not a hardware fault.

I went to the hangar later that day and called him, he helped me reset it through the G5, took 3 minutes. I was so happy thinking it might mean I was going to need a servo?
I have flown it about 5 hrs since then and the trim is working like normal. I have almost 800 hrs on the AP. It is nice to have dealer to help you, well worth what I paid him to install it.

My dealer does any updates whenever my plane is there, shop is local.

I picked up my buddy earlier this year at the avionics shop after dropping off his plane for panel work. The dealer(Scott) saw it was me and said what version are you running on your G5? I looked and he went out to my plane and updated the G5s while I watched. Took just few minutes.
Had no idea my plane was going to get free service when I went over there.
 
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I thought Garmin wanted you to get tech support from a Garmin dealer?

I have local dealer who is a Garmin dealer who installed my panel that I get tech support from.

Last week I started my plane with the avionics switch on, and it created a Ptrim fault. A red ptrim window came up on my G5. Message said ptrim clutch fault. Electric trim quit working and no pitch on my AP. Bummer...

I called my dealer for help and he said we may be able to reset it since it is a clutch fault and not a hardware fault.

I went to the hangar later that day and called him, he helped me reset it through the G5, took 3 minutes. I was so happy thinking it might mean I was going to need a servo?
I have flown it about 5 hrs since then and the trim is working like normal. I have almost 800 hrs on the AP. It is nice to have dealer to help you, well worth what I paid him to install it.

My dealer does any updates whenever my plane is there, shop is local.

I picked up my buddy earlier this year at the avionics shop after dropping off his plane for panel work. The dealer(Scott) saw it was me and said what version are you running on your G5? I looked and he went out to to my plane and updated the G5s while I watched. Took just few minutes.
Had no idea my plane was going to get free service when I went over there.
My dealer will Garmin for assistance... but they are not open until tomorrow...
 
I don’t recall what function I added to mine but when it didn’t work, I called Garmin. They asked what it was doing and once I described the odd behavior, they told me I had pinned the leads into the wrong connector. They were right, too. Those are smart folks in tech support.
 
Something is up with the GX3 and the GFC500. Scott asked me first if my GFC was controlled by a GX3. I said no of course and that is when he asked about my G5. He did mention some concern between the 2.
Good luck with it, I would bet your dealer can help?
 
I don’t recall what function I added to mine but when it didn’t work, I called Garmin. They asked what it was doing and once I described the odd behavior, they told me I had pinned the leads into the wrong connector. They were right, too. Those are smart folks in tech support.
Was your AP (GFC500) working fine in flight before the issue?
 
That issue had nothing to do with my AP. It was probably when I added fuel pressure. Wiring additional senders into an installed G3X is an adventure. The point was that Garmin will help you find a solution.
 
Want to document some things I found out, in case it helps anyone else in the future:
During install a shop will most likely have to update the firmware, therefore when you get a plane from the dealer there should be no wiring issues
For operation the CAN bus has some more error tolerance than for updates
Beyond pulling all breakers, need to ensure all switches (light) etc are off
Lastly, in my case the issue was the GPU introduced some ‘noise’. Despite the Garmin advice to use a GPU, not using one did the trick for me.
If all else fails last resort is to run a dedicated direct cable from G5/G3X touch to the GSA29
 
If it were my plane, I’d have the wiring redone until updates can happen properly. I would not accept a high error rate on the CAN bus. Just because it’s “good enough to work” doesn’t mean it’s working optimally, or that you won’t one day get a little worse, and then it’s not “good enough” anymore and you start to see random unexplained behavior.
 
Tim, you’re saying a back-up battery was the source of your problem? What kind of back-up did you use? My data and OS updates are done using my TCW BBS to power the unit. In fact my G3X is powered through the BBS 100% of the time, but updates are done with the Master off. Never any hiccups.

Updating software is simple on my exp unit. You need is a separate SD card. The instructions say not to use the same SD that’s used for data updates. You can upload the OS without a paid subscription like charts require. I believe you certified guys are on v9.01? Exp guys are on 9.0. The only “trick” to updating is providing enough time for the unit to complete it.
 
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If it were my plane, I’d have the wiring redone until updates can happen properly. I would not accept a high error rate on the CAN bus. Just because it’s “good enough to work” doesn’t mean it’s working optimally, or that you won’t one day get a little worse, and then it’s not “good enough” anymore and you start to see random unexplained behavior.

Sure thing. You’ve never done it though, right? I remember the first time I turned mine on. It didn’t work properly. My mechanic took a few minutes to read the wiring instructions and realized he hadn’t terminated the CAN bus. That was my first time chasing little wires and pin-outs in the installed and buttoned-up airplane. Not as much fun as you might think.

06407192-D922-4438-BAB7-B48850E7C732.jpeg C191EDBB-C2D1-4442-A6F6-B675FDAA345D.jpeg
 
I have done it. dual G5's, GMU11, GAD13, GAD29B, and GFC-500. Yeah, it's easy to mess it up. Yeah, it's a nightmare to find the problem. Patience and following the instructions and doing it right the first time make a big difference. This is why I wired it myself. Drew a full diagram first to get a good understanding. Things you don't get when you let someone else do it for you, though a good shop will make and give you a diagram.
 
If it were my plane, I’d have the wiring redone until updates can happen properly. I would not accept a high error rate on the CAN bus. Just because it’s “good enough to work” doesn’t mean it’s working optimally, or that you won’t one day get a little worse, and then it’s not “good enough” anymore and you start to see random unexplained behavior.
The wiring is done properly, there is 0% CANBUS error during normal operation.
The GPU introduced 'unclean' energy

Tim, you’re saying a back-up battery was the source of your problem? What kind of back-up did you use? My data and OS updates are done using my TCW BBS to power the unit. In fact my G3X is powered through the BBS 100% of the time, but updates are done with the Master off. Never any hiccups.
I have this GPU:
Aviation Ground Power Unit 28V GPU | Aircraft Spruce
needless to say I am a little bit unhappy that this 'supposedly' high-end GPU causes 'noise' in the electrical system preventing the update to run properly.
Also noticed there is a buzzing sound in the headset while the GPU is in use
 
Do you have a battery backup-power conditioner in certified installations? Sometimes I attach a battery charger for uploading charts but I’ve never had any problems. I can’t say whether my BBS is helping or not. I understand your frustration and am glad to hear you figured it out.
 
Do you have a battery backup-power conditioner in certified installations? Sometimes I attach a battery charger for uploading charts but I’ve never had any problems. I can’t say whether my BBS is helping or not. I understand your frustration and am glad to hear you figured it out.
The G5 has a battery, but nothing else does.
For the one servo there is no issue running it off the plane battery.

My frustration is really with the GPU, as it is made to reduce 'noise' with modern avionics. Mailed the MFG, if my unit has a defect or if that is normal.

And I am going to get a battery minder connector wired during next annual, which may allow the battery minder to be online during updates.
 
Do you start your G3X before engine start? Guys I know do, and I do, as well. Without a power conditioner/backup source, the engine start interrupts the power and the G3X restarts. I’m not familiar with certified installs. How do you deal with start-ups?
 
Do you start your G3X before engine start? Guys I know do, and I do, as well. Without a power conditioner/backup source, the engine start interrupts the power and the G3X restarts. I’m not familiar with certified installs. How do you deal with start-ups?
G3X touch is the primary for all my instrument gauges.
Therefore it starts with the main power, as I need to see fuel flow and oil pressure for engine start.
When cranking it does not cut out, it stays on just fine.
 
Do you start your G3X before engine start? Guys I know do, and I do, as well. Without a power conditioner/backup source, the engine start interrupts the power and the G3X restarts. I’m not familiar with certified installs. How do you deal with start-ups?

Certified G3X installs w/EIS on a 14v aircraft require the use of the GAD 27 to stabilize power, this prevents the drop out during cranking, it's optional on non-EIS installs.
 
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