WNRO (week number roll over) bug once battery removed

[tt8484]

Hi,

This is to inform the community that zumo 660 (perhaps even 665) fails to handle the GPS WNRO of april 6th 2019.

The issue occurs when you remove the battery even just once, causing the proper date to be lost forever. Upon reacquiring sat signal, the time will be right, but the date will be wrong (about 4 month and a half later, in 1999).

Trip logs will be incorrectly date stamped. Ssunset/sunrise times are wrong and day/night mode to turn in at wrong hours. The time zones rules cannot be applied (probably because 1999 is out of valid range) - this is (in)visible in the world clock app, and you cannot have auto time either. The DST change is expected to have issues too, but we cannot know until june 16th when the pre-2007 october DST rule should apply.

Links to german forums (add language to Chrome to translate pages):
http://www.gs-forum.eu/navigation-113/w ... er-153771/
https://forum.garmin.de/showthread.php? ... nz%E4hlung

There is no fix available yet. Latest firmware version is still 5.10 (june 2014).

[carolinarider09]

Just verified your information is correct. Zumo 660 shows my last route (which was logged yesterday) says 20-SEP-99 with correct time. Looking back at trip log shows April 25 as 2019, with the next segment (unknown when for sure) as Sept 17 1999. I will have to check and see what my 550 shows.

In my case, the battery fell out when I was uploading some files to the device.

[Wingstyle]

Same here on my 660. Track logs Sept. 1999. I took my battery out to get to my micrSD card. Tracks not such a big deal for me, but the sunset/sunrise and DST will be a pain. I hope Garmin can fix it with a FW update.

[danham]

Thank you very much for posting this. I was about to pop out my battery to transfer a bunch of routes for an upcoming trip to my micro-SD card. After reading this topic, I will definitely put up with the glacial USB transfer instead and be very careful not to jiggle the battery while doing so.

-dan

[danham]

Has anyone tried connecting the zumo to a power supply and then removing the battery? Does that prevent the problem?

-dan

[tt8484]

Has anyone tried connecting the zumo to a power supply and then removing the battery? Does that prevent the problem?

I wouldn't try on a PC connection because of the fear of crashing the internal or external SD card filesystem.

On a mere power charger, the gps didn't loose its current time, so I guess it's ok.
The gps says "insert battery". I suspect it would just NOT be operable with the pc anyway.

Besides, the chances are high that a glitchy contact of the usb cable would cut all power; you would have to be super careful to get the sd card out/in without disturbing the usb power cable, but that appears possible. Perhaps doing it in the bike's cradle (or even the dashboard mount you probably never used) would be safer..

[alan sh]

But I assume we can reset the time somehow if this does happen (can't we?)

Alan

[tt8484]

But I assume we can reset the time somehow if this does happen (can't we?)

Alan

no, we can change time (hour and to 15min error) but we cannot change the date. that's the whole reason this is a major bug.

(I hoped the recent garmin express update wold have brought a workaround like maybe a proprietary talk with the device to reset the date, but that wish didn't come true. I guess there is just no internal set-date API on that firmware, but I'm still hopeful).

[adl55]

What's with the "once battery removed" anyway? Is that fiction?

My battery hasn't been removed in years. My Zumo 660 has been powered up several time a week all year -- whenever my car is started. (Move it to the bike for riding.) Yet it's been 1999 again since last month.

Updating the firmware two weeks ago did not, as I'd hoped matter. Since then, I've found the Zumo to be less than reliable for navigation. Should NOT be due to the new mapset based on the roads it can no longer find. Frustrating!

Is there any hope that Garmin will do something about this?

[danham]

...Updating the firmware two weeks ago did not, as I'd hoped matter. Since then, I've found the Zumo to be less than reliable for navigation. Should NOT be due to the new mapset based on the roads it can no longer find. Frustrating!...

Did you do a master reset after updating the firmware? It is not surprising that the bug would occur under the old firmware, but perhaps the new firmware has not yet been able to address that part of memory until you do the reset. Also, the navigation glitches are another symptom of needing to do it after a firmware update.

Just a guess, but hope it helps.

-dan