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Garmin GNC355 Position.

Jpm757

Well Known Member
Everytime I power up my GNC355 (same navigator as the 175 and 375), it still thinks it is at the factory in Kansas. Consequently it takes longer than my Dynon unit to acquire a GPS signal. For some reason it does not remember it's last known position. Any ideas? Thanks.
 
I think all these navigators have an internal memory to remember where they were last, and that memory is powered by a small internal battery that eventually needs replacing. Perhaps yours was dead on arrival. Call the dealer.
 
Check the config module

Everytime I power up my GNC355 (same navigator as the 175 and 375), it still thinks it is at the factory in Kansas. Consequently it takes longer than my Dynon unit to acquire a GPS signal. For some reason it does not remember it's last known position. Any ideas? Thanks.

These new units from Garmin have a little config module that is a small circuit board you plug a 4 wire harness into one of the back connectors and you put it in the connector shell. These modules are the place that stores your unit setup settings, so if your unit is replaced, you still have your settings. It might also be where your last position is stored.

So was the config module installed and correctly? If not, check that out. Yes, it can be a bad internal memory battery, but being new, that is a slim chance, but possible.

I have installed 6 of these units and never had a problem, but the first time it does take a bit before it gets a position lock on, so until it does lock on, it will still think it is back in Kansas.

Good luck.

Brian
 
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These new units from Garmin have a little config module that is a small circuit board you plug a 4 wire harness into one of the back connectors and you put it in the connector shell. These modules are the place that stores your unit setup settings, so if your unit is replaced, you still have your settings. It might also be where your last position is stored.

So was the config module installed and correctly? If not, check that out. Yes, it can be a bad internal memory battery, but being new, that is a slim chance, but possible. Good luck.
+1 Brian! I've been immersed in the GNC355 Install Manual for the last few days planning my own 355 installation and I wholeheartedly agree with your assessment and suggestions to JPM757.

Like the GTX335 w/GPS xpdr, the GNC355 needs either a configuration module or a GAE12 encoder to remember the most recent GPS position. My guess is the configuration module (or GAE12) is missing or improperly installed or configured.

I have installed 6 of these units and never had a problem, but the first time it does take a bit before it gets a position lock on, so until it does lock on, it will still think it is back in Kansas.
Brian
I'm new to the forum and don't want to hijack JPM757's thread but I am curious Brian, if any of the six GNC355 installations you've done have interfaced the GNC355 with a GTX335? If so, I'd like to ask you a few questions either here in this thread if appropriate or perhaps in a new thread or in a Private Message.

Please let me know! ZT
 
I'm new to the forum and don't want to hijack JPM757's thread but I am curious Brian, if any of the six GNC355 installations you've done have interfaced the GNC355 with a GTX335? If so, I'd like to ask you a few questions either here in this thread if appropriate or perhaps in a new thread or in a Private Message.

Please let me know! ZT

ZT,

Email me at [email protected]

Brian
 
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GNC 355 Position

Everytime I power up my GNC355 (same navigator as the 175 and 375), it still thinks it is at the factory in Kansas. Consequently it takes longer than my Dynon unit to acquire a GPS signal. For some reason it does not remember it's last known position. Any ideas? Thanks.

Good Morning,

We are working on trying to recreate this issue on our bench. Is the GNC 355 showing your position on the moving map page as being located in Kansas? It is not unusual for the navigator to take longer to fix a GPS position, than an EFIS would, but the GNC 355 should not boot up as if the aircraft is located in Kansas on each power cycle. Can you send us some pictures of this happening to [email protected]?

Thanks,

Justin
 
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