Etrex SE/Solar fails to save track history in cold weather (835)

[gps_techie]

With eTrex SE/Solar, after a long trip outside in a cold weather (below -5C), saving track history to memory fails in some cases. That is, select track->save->confirm, screen shows black background with word "saving", then screen becomes blank and eTrex SE/Solar resets. After reset track history is lost :( Previously saved tracks are still in memory.
I suspect it has something to do with cold weather and saving requiring more current.

FW 4.25

[GPSrChive]

Has this been duplicated with both models?

What was the battery level in each at the time?

Which brand/model of batteries were installed in the SE?

[gps_techie]

~25% of saving fails with reset on either SE or SOLAR (randomly). Noticed this in cold weather. Still not sure what exactly is happening.

SOLAR shows ~52% left. SE shows full bars, under load AA battery has still high (1.42V) output. Simply Duracell AA alkaline batteries, still valid till 2027. So in theory enough juice left.
Maybe in low temps internal resistance increases and undervoltage condition occurs during save step. Maybe 52% is an overestimation. Detailed current measurement of saving step is needed to check this, on SE it is easier to do than on SOLAR.

[GPSrChive]

Definately should be running lithium AA in those temps, alkaline will choke.

What was the actual ambient temperature?

[gps_techie]

eTrex SE failed to save again, resets actually happens after save screen stage, i.e. select track->save->confirm, screen shows black background with word "saving", goes back to time/distance saving display and only then screen becomes blank and eTrex SE/Solar resets.
Temp was ~-5-12C outside, but depends on moisture/wind/etc. Tried saving after ~20minutes inside, SE AA bateries did not even feel cold to the touch.

eTrex Solar with internal li-ion battery also fails sometimes, so I am not sure that batteries are the direct issue. Both SE & Solar are rated for low temps, but something fails.

[GPSrChive]

Yes, you certainly are just within the published operating temperature limits.

Please make complete copies of the Debug folder from each device and send to address below. If you zip them, they become much smaller and easier to share!

@

webmaster@gpsrchive.com

[gps_techie]

Debug has some info, take a look.

[Marko]

My two cents...

Was naviagation of the course active during of the activity saving?
I've noticed that my new eTrex SE suddenly reboots when navigation is active (with 199 course points though). So, I'd highly reccomend to stop navigation before saving an activity. I usually ride close loops, therefore my navigation often stops automatically before saving, though. It may not be the case, but it's better to check...
BTW, it's much better to use a 'track' (with unlimited number of points) then a 'route' (with <= 200 course points), also due to memory choke phenomena. The first option starts within a few (2-3) seconds, whereas the second option is a little bit slower (but certainly < 1 min.).

[gps_techie]

No navigation was running during activity, just recording track history.

[Marko]

Maybe it was a memory case, Independent of łów temperature?
If may I ask...What was the Registration Mode: Smart/Every Seconds? What was the free memory left?
How much time last your trip?