GPS function of navnet



I have a navnet vx2 unit in my boat. Just this past week while fishing here in Alaska I was tracking my path and then the tracking stopped and when I got back to the marina I powered the unit off and then back on a few minutes later. The track that was on the screen went from the marina to the place it stopped tracking then to Osaka Japan and then back to the marina. I did try to use it again and it would come in and go out and then stop all gps functions. I did order the upgrade antenna for the unit but have not received it yet.
Anybody had this problem or know what happened to my unit.
Tracks will drop where your unit is plotting your location.

If you GPS has issues finding your location it will default to location setup under your GPS setup page. If that default location is in Japan; that will be your boat location until GPS is received. Any tracking will follow that boat position if your tracking is turned on.

As you know repairing the GPS issue is the best solution but you can help things by changing the default location in your settings. (MENU - SYSTEM CONFIG -NAV Option - GPS Sensor Settings - Enter the Lat/Lon of your local area in the LAT & LON entry blocks)
Hi C SCHREIBER, Do you or Johnny know what the actual problem and resolution was?

My Navnet Chartplotter (1833C) just had a senior moment and did almost exactly the same thing.

From the symptoms (system crashes, chart not painting properly, loss of memory - waypoints and mark/routes gone, GPS jumping from Osaka to home and back every few seconds, not able to access GPS sensor settings etc I would have picked one or more of a power supply problem, chart sim failure, internal memory error, GPS unit Failure etc. But the symptoms just seem a little too broad to be just one thing.

I would really appreciate you taking the time to tell me what you found and how you ultimately fixed it



PS My system is running, The radar and Sounder work fine (when the processor is not working hard jumping from Osaka to NZ and back), the chart works after a fashion but wont let you zoom in very far (loses the land colour) and the normal settings like display background colour dont work properly, overlay works so the heading sensor is still operational, I have checked connections, supply voltage,done a display unit test which tests OK for Memory, internal Battery etc, The Internal battery tests at 3.08v (no load)
Johnny Electron":24x8635g said:
Start with the simple things.
What is your full software program number?
Hi Johnny

I like Kiss, luckily I took a photo of the test screen yesterday else I would have to visit the boat to get your answer, so Program number = 1950002016

Full test screen in attached picture


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I Have to say I favour the GPS sensor or cable failing as I had similar symptoms (not able to complete a module test test) when my network cable failed through corrosion, the Display would intermittently not connect to the network sounder and would not allow you to enter the Network sounder test screen or settings, I replaced the network cable and it all came back to life (nothing in the User manual about that!)

Seems strange how it has affected the tracks and marks memory (all gone) and the chart detail though, as far as I can tell the system has completely defaulted which is a real shame as all that history is gone... :angry , Johnny where are the track and marks saved? SDRAM, SRAM, the chart SIm, or somewhere else?

Tracks and marks are saved it the units memory along with any backup you have made with the older memory card backup card or PC. If you don't have a backup, then the data isn't recoverable.

Your software is Navionics version 16 (2003) for the NavNet series one. The software predates the newer GP320B (aka BBWGPS) antenna. You would need to send the unit in for have your dealer update the software. The newest version at the service center is version 26. At ten versions behind on software, I would also guess that no one has done the required internal battery change. I would recommend you send the unit in for repair evaluation and software update.