No GPS signal on Chartplotter

[Nudge]

Need some help problem solving a GPS reception problem. I have no GPS signal on my Chartplotter. The dreaded no satellite signal question mark has appeared on my vessel.
There is no way to ask the make the GPS reacquire satellites that I could find in the Chartplotter manual.
Chart plotter is a Garmin 7215
Antenna is GA 30 GPS
Both original equipment on my 2013 RT 29.
GPS has worked with no problems until now.
Steps taken so far:
Replaced the GA 30 with a GA 38. Still no signal reception.
Verified there is power to the antenna.
Cleaned the BNC and antenna connectors.
Still no signal reception.
Checked Garmin marine support center. Recommendations included unplugging power for at least 5 minutes to let built up charges discharge. Did that twice: once for 5 minutes, once for 30 minutes. Still no reception.
Disconnected the power cable, the two network cables and the NMEA 2K cable from the back of the 7215. Waited 10’ and turned system on. Still no GPS signal.
The only thing left is to disconnect the power cable from the NMEA backbone itself. Is that necessary? To get at it I will have to dismantle and remove the back closet in the forward berth in order to access the NMEA backbone.

 

[bob daily]

You said this problem just appeared, are you in a covered slip? Or is there other obstructions that could cause this loss? Just wondering.

 

[Nudge]

HI Bob, Yes, Nudge is in a covered slip and his been since we bought her in 2013. Never had the problem before. The AIS functions fine-- plotting other AIS targets on the chart plotter and the GPS data shows up on the GHC-10 giving proper heading. There are no new instructions. I'm stumped!

 

[bob daily]

Fred, is the simulator mode turned off? If the simulator mode is accidentally turned on the unit will not track satellites. From the home screen select Configure > System > Simulated > Off
Just something to check. Bob

 

[bob daily]

Another option is to reset your unity back to original factory settings (page 119 of your manual) you will lose all your information and have to start all over setting up your unit but if you get satellite reception might be worth the fix. If that doesn't fix it it might be time to replace! Bob

 

[Nudge]

Thanks Bob. I checked and the Simulator was off. I'll be calling Garmin and see if they have any suggestions short of restoring to factory settings. Hmmm, need to review how to copy routes and waypoints to a card! Fred

 

[gulfcoast john]

Fred,
I’m surprised Garmin tech support didn’t suggest a plotter software update with a new antenna on a ‘legacy’ plotter.

https://www.garmin.com/en-US/support/software/marine/

Under “Legacy GPSMAP Series with SD Card” and follow instructions to download on your SD card.

The update includes ‘Communications.’ The SD card should be formatted 32G, not over. I”ve had this cure issues even when I have not added any devices on my legacy twin 8212’s. Don’t lose 12v DC power during the process ie be at the dock with battery charger on and no one else flipping switches.
Might be worth a try…
Yes, you can export (and import) waypoints onto a <32G SD card, just follow instructions carefully.

If you can find an option on the 7215 to ‘list all N2K Devices’ does the GH 38 show up?

Good Luck!

John

 

[knotflying]

I have seen this problem before. It could be the antenna or the wire from the unit to the antenna or the connections. Make sure the connections are clean. If no joy then you could get a new cable and run it from the unit through the window up to the puck. If it works it is the wire. If it is the wire then you have to make the choice of either running the new wire concealed or get a shorter wire and place the puck inside the cabin with as little overhead obstruction as possible. If it does not work it could be the puck.

 

[KennyMarrs]

Hey Nudge,

I can't say I remember us ever installing a GA 30 or GA 38 antennas. I believe we've only installed the 19X. Regardless, either antenna should show up on your devise list for the NMEA backbone. That would be my first check to see if the antenna is recognized or not. I would also do the reboot out of the covered slip.

 

[Nudge]

Thanks John- I updated the firmware last spring and all systems worked afterward. Going to download again this week and try it next visit to the tug. Also going to copy may waypoints and track lines to a chip before restoring to factory settiongs...if it comes to that. Waiting for a response from Garmin before I take further steps. Fred

 

[Nudge]

Hi Kenny--Boat came with two GPS 30 antennas: one for the plotter and the other for the AIS.

 

[MoonshadowLP]

Hi Nudge - I'm having the same issue so I'm really curious if you found a solution.