Garmin 855 keeps crashing

How much free space is in the internal storage? Are you using custom POI's with Proximity alerts? Do you use the MP3 player?

One quick thing to try is to clear the trip log. Also remove voice files and speech recognition files for unused languages.

Probably the best thing to try is a system reset. It is a little tricky on the 8x5 nuvi's so let us know if you need help with the procedure.

For the reset, look at
How Do I Perform A Master Reset On My Dezl/Edge/Live/Nuvi/Quest/StreetPilot/Zumo

The most likely culprit are the alerts. The processors are pretty weak and the software has a lot of bugs. The unit can normally do two voice announcements back to back or overlapped, but add a third and it freezes. It mostly happens when it is playing an alert and then gives a routing direction.

You can also hold the power off for about 15 seconds and it will do a cold boot, just as if you removed the battery. The only solution is to use just a very few alert announcemnets.

We would love to know how much free memory you have. As already stated, not having enough memory often causes devices to do funny things.

The 855 can't install all of North America internally and isn't auto-offered the update to SD card. To get the full map on the SD card, the clone method must be used.

How big is your map (go to Map Info and tell us what you see, checked, or unchecked) and whether your map is internal or on a SD card.

All in all, right now I like best the "too many simultaneous alerts," especially if some alerts are TourGuides or if your audio alert is a mp3 file. With my 855, I had many fewer freezeups after I switched my audio alerts to wav files.

I also have experienced the daily crashes. My crashes have been almost always the "spontaneous reboot" variety. The reboots are always associated with an alert. There also seems to be a sensitivity to the map version; with one map version the 855 may regularly reboot at a specific alert location, while not rebooting with the previous or later map version. No correlation with "single" or "multiple" alerts (I'm rarely navigating, so there are no voice routing directions occurring when the 855 reboots, just a single POI alert). My gut feeling was the reboots were related to the mp3 audio alert, but was never able to prove it. I did recently change the alert sound from mp3 to wav (using SOX), but continued to have the spontaneous reboots. A weak processor combined with multitasking/multithreading bugs is a plausible explanation for the reboots.
Mark

For what it's worth, I always have been able to install the full North America version on my 855. Map Info shows on the first line (checked): "CN North America NT 2015.30", and on the second line: "[1] ALL". The map files are installed on the internal memory. I have removed most of the vpm files and put the large jcv file on a uSD card. The only files on the uSD card are the large jcv and some mp3 music files. I show 307806208 bytes free (of 3.4GB). I have ALWAYS had the reboots, even with much smaller maps versions and junction view files.
Is there any consensus as to the amount of free memory that is required?
Mark

The memory is 91% full. I only have 2 voices installed and I don't use the MP3 player.
I will check on the trip log and maybe do a complete reset.

@wayne, I assume the above is about a 855 device. However, your profile indicates you have a 2450 (so it would help those answering questions to be able to look at your profile and determine which units you have).

The 855 has 4 G so it would look like (with 91% used) that memory is not the main problem.

Others are indicating that their units freeze when playing alerts. That was not mentioned in your case. As you posted, it just seems to "lock up".

Does there seem to be any pattern as to when it locks up?

I do have a 2450 and a 855. In fact, I bought the 2450 to replace the crashing 855.
You say it could be caused by playing alerts. Yesterday it crashed while it was muted. Maybe it doesn't matter if the sound is on or off.
I'm beginning to wonder if it is heat related. It seems to work better if the dash is in the shade vs a hot sunny dash. Also, it never crashes while the car is not moving, just going down the highway in the sun.
Thanks everyone for your ideas.

with my 885 was the software could not handle three simultaneous calls to the voice routine. It would still make the calls if the unit was muted. Reducing the number of alert messages cured my unit from freezing (with some rare exceptions) and I had no problems with the heat as the unit sat on the dash in a bean bag mount.

Could you explain how to reduce the alert messages?

Remove the MP3 or Wav files from the POI you load.

While I still own one I have not been running my 855 since I got a 3790 LMT. While my 855 was a huge upgrade from the GPS V which preceded it, the seemingly random freezes roughly once every 10 hours of operation throughout the life of the unit were a pretty serious annoyance. It also would do full-fledged spontaneous reboots once in a while.

I attributed both to software flaws, and was not able to notice any particular repeating condition that trigger them.

The 3790 LMT has not been entirely free of freezes in my ownership, but they have definitely been far less frequent.

I have had all these problems at various times with my 855. Like Box Car, it was usually caused by too many alerts in close proximity. It is especially bad if you use Tour Guide alerts with fairly large distance in areas that have a high POI density (like large cities). I also noticed that the problem was worse when using the MP3 player in addition to the alerts.

I was able to make my 855 trouble free (almost) by eliminating some high density alerts, reducing the proimity distance and changing some Tour Guide alerts to proximity alerts. I used the 855 as my primary GPS unit for about 4 years and was very happy with it overall.

I think you're right. In an ongoing thread about loss of storage on a nuvi 2797, we've seen that during map updates when the speech recognition files are updated to work with the new map, that sometimes, the older speech recognition files are not deleted even though they're not needed and each set of srx/asr files total about 775MB. I had two sets of uneeded srx/asr files totaling over 1.5GB! I've now deleted these files and will try to install all of 2015.40 when it soon comes out. Thanks for your tip. I'll report back after the map update. Like you, I also use the large jcv file on the nuvi 855 and will likely have to keep it on the SD card.

My 855 is like a rock in comparison to my 3790 which was replaced by Garmin once.
I carry it with me on my trip to and from Mexico just in case the 3790 craps out.
I've removed any files I do not need or use including MP3 and also have the large JCV file on an SD card.

My 855 first crashed when driving north in Fl coming home in Jan 2010. I got it Sept 2009 and had done some long trips in Northern Ontario with no trouble. Since then it has crashed quite a few times. I have NO proximity alert installed.

I have noticed that it seems to to crash when I have been using the mp3 player in shuffle mode and it is a sunny day.

My conclusion is that, as the unit heats up to something above 100F, there is a problem with the timing between the mp3 read/write and the cpu. (Note the the sun through the windshield can easily heat the unit to above 100F depending on your cooling air flow.) I now mount the unit between the front seats and do not use the shuffle function. So far no real problems.

However, I have noticed something that may be analogous to overlapping alerts. Continuous "recalculating" and directions to take specific streets, when the blocks are VERY short, does overwhelm the cpu. For me me, this is a very rare occurrence.

btw, my memory cards are full. I have the latest complete NA map, a UK map and about 30 hours of music on my main memory and SD card.