Garmin has identified a bug in some new Forerunner and Edge units (205 and 305) that cause them to lock up after a full charge. Here's a temporary fix until the next software update:
"To power the unit back on, press the "Mode" and "Reset" buttons at the same time. Let go of those two buttons, press the power button, and the unit will turn back on."

I had this problem with the first Edge Unit I got... I didn't realize there was a workaround. The unit just freaked out on me and I couldn't get it to turn back on... I eventually took it back to the shop where I bought it, and the unit turned on for them. The shop was cool about it and exchanged the unit.
Here's the problem, my second unit, doesn't seem to properly record altitude info... Is there a fix for this problem?!
Posted by: Brad | March 28, 2006 at 08:54 PM
I like the Edge, but I continue to be frustrated with the short battery life. It dies sooner than my Forerunner 305, which I continually had problems running out of battery life on long rides. At least I could get 12-13 hours on the Forerunner. With the Edge, I start getting low battery signals after 9 hours and it dies just over 10 hours. I've already shut off my cadence option in an effort to prolong the life. Any other suggestions? Thanks!
Posted by: Wayne | March 30, 2006 at 07:51 AM
Wayne,
Every battery/unit is likely to perform a bit differently - no two alike scenario. Turning cadence off should not have an affect on battery life of the Edge.
Garmin has not received complaints about batteries not lasting at least 10 hrs. If the battery continues to drain out before 10 hours, you should contact Garmin Product Support to get a replacement unit.
Keep posted for a post to our blog in the next week... the MotionBased crew has been hard at work to jerry-rig a battery extender for the Edge.
Posted by: Clark Weber | March 31, 2006 at 08:35 AM
I seem to only get about 6 hours out of my edge 305. I have been emailing support at Garmin and have yet to get a reply.
They were great about replacing the HR strap that didn't work however they have been silent regarding my battery question. Thoughts?
Posted by: corwinmd | April 15, 2006 at 05:58 PM
I seem to have to do this mode-reset-on key sequence quite a lot. The problem for me is that when the unit does power on after doing this, the unit thinks that the battery is fairly low 1-bar in the little meter. Then when I ride with it after this, I get a low battery warning after about an hour and a half. Then the unit shuts down as if the battery is completely flat after a few hours. Is this a hardware bug where it also drains the battery when it gets into this funky problem mode?
Posted by: neb | May 13, 2006 at 07:06 PM
I just bought the 305Edge and I'm so disappointed with all the hardware bugs. I hate mode-reset problem, it happens a lot and like you said the unit displays a low battery charge after it has been charging all night! This product just needs to be recall!
Posted by: cz | May 30, 2006 at 05:21 AM
cz,
You should contact Garmin Customer Support to get a replacement Edge - http://www.garmin.com/contactUs/techSupport.jsp
Posted by: Clark Weber | May 30, 2006 at 09:48 AM
This locking up in understandable--new items have bugs. But the silence on this issue on Garmins's website is inexcuseable. Someone at Garmin is ruining the reputation of a great company by ignoring this issue and, at least, not putting up the workaround described here.
"To power the unit back on, press the "Mode" and "Reset" buttons at the same time. Let go of those two buttons, press the power button, and the unit will turn back on."
I had packed up my Edge 305 to return it and then found the workaround posted here on motionbased.com and absolutely nothing on Garmin.com
Posted by: paulzane | June 04, 2006 at 03:04 PM
I agree with Paul Zane - when marketing concerns override the support of existing customers ("you know - we are the one's paying your wages") it is inexcusable.
I just experienced this problem today and only by searching for "reset garmin edge 305" did I find this page. Should be on Garmin's FAQ pages - but that would be admitting something below perfection, and when you are facing competitors that cannot of course be right. Sarcasm intended - for those who are not used to it.
Posted by: Peter Galbavy | June 08, 2006 at 12:51 AM
I have trouble getting my Forerunner 305 to charge... When I put in the craddle the unit turns on. I can't get the unit to charge at all... The charging in progress screen will not come on at all... I turn the unit off in the cradle and it will just power back on and give me the low battery indicator...
Any ideas
Posted by: Mark Livesay | June 17, 2006 at 02:11 PM
I agree with Peter, I've also had my Edge305 lockup after a nights charging.. the signon screen would show, and instead of looking for satellites, it would turn off. I put it on charge, but the power went off during this and caused a total lock out - not even the signon screen, and it's only after finding this blog that I can get it working again (good thing to, I have a long ride coming up on Sunday). I think Garmin should include this problem in their FAQ... I reloaded the s/w (v2.60) and it had most of the battery bars on the display. My battery life is also about 6 hours - do these battries need to "bed in"? I've only charged the thing twice so far.
Posted by: Gordon | June 23, 2006 at 12:21 PM
My unit will not unlock with the Mode/Reset then power on fix?
Posted by: Rossy | July 15, 2006 at 01:55 PM
Rossy,
What device do you have?
Posted by: Kathryn | July 20, 2006 at 11:47 AM
Does anyone have -- or know where one can find -- a Macintosh workaround
so I can use a Garmin Edge 305 cycling computer along with MotionBased
(or TrainingPeaks) software? Many thanks!
Posted by: mindy | October 08, 2006 at 07:31 PM
Mindy,
Plese follow the instructions on this page...
http://wiki.motionbased.com/mb/Mac_Web_Agent
Posted by: Clark Weber | October 09, 2006 at 10:29 AM
Forerunner 305 not recording altitude properly. Garmin said to return it, a friend has done this 2 times and hasn't got a good read on altitude yet.
Anyone else? My Garmin Forerunner 301 worked much better, as long as I wasn't under trees. Help.
Posted by: cathy | October 12, 2006 at 04:23 PM
Hello:
Can you help to solve a problem that I have with my Forerunner 305 ? The unit doesn't respond when I press the mode button or it does it just making a big pressure over the button.
I think it has a mechanical fault and maybe if I could open the unit I could fix it, but I don't want to damage the case.
Thanks,
Claudio.
Posted by: Claudio Pavanati | November 19, 2006 at 03:37 PM
About to-lock-up-after-a-full-charge problem: my unit doesn´t work when I press the "Mode" and "Reset" buttons at the same time, let go of those two buttons, and press the power button. No answer at all.
Posted by: Javier | December 13, 2006 at 09:35 AM
Hi Javier,
I've contacted the appropriate Garmin support staff. They will be in contact with you soon.
Kahtryn
Posted by: Kathryn | December 13, 2006 at 03:49 PM
Hi Javier,
I received the help/answer from the Garmin support staff. We recommend that you try the reset with external power applied (USB cable). If this does not work the device would need to be sent in for repair, depending on where he is on the globe and/or an exchange through the dealer he purchased it from.
Keep us posted.
Kathryn
Posted by: Kathryn | December 14, 2006 at 02:45 PM
Hi all,
I have had a similar problem with my Forerunner 305 locking out (unfortunately, I then became lost and spent 2.5 hrs wandering around a forest!).
It would only boot up and present the 'splash' screen for about 3 seconds before going dead again. I had tried all the work-arounds mentioned here but to no avail. I ended up contacting Garmin Hotline and they suggested trying a similar workaround:
Press MODE and RESET together, release just the RESET button and continue to hold the MODE. Now press the POWER-ON still holding the Mode button.
This boots up the Forerunner into an 'erase all?' menu.
This also only stayed on for 3 seconds before powering off. After afew attempts at this, I managed to select Yes to the erase question (within the 3 seconds) and the unit rebooted and now works fine again. (All data was erased along with any version updates)
Hope this helps anyone with a similar problem.
Kevin.
Posted by: Kevin | January 08, 2007 at 07:23 AM
Hi All,
In the middle of a ride with my edge 305, the screen suddenly changed to a warning about 'anomalous power source' and a two-tabbed page with data of some sort. I remember one of the tabs said 'stack', can't remember the other one. I stopped, pressed the 'Mode' button and everything went back to normal -or so I thought. After this incident, the Edge is fine but it's no longer recognised by Training Center. It is, however, recognised by garmin Gstart, that launches TC normally. When I try to download/upload info I get a 'check the connection' message. The connection is fine, of course. I have updated the software and the chipset to 2.90 to no avail. Any ideas? Thanks a ton!
Posted by: Emilià | February 04, 2007 at 03:17 AM
There was a problem with V3.2.1 of Training Centre. Basically if you uploaded your COURSES from TC to the 305 (I have the Forerunner), it then stops responding for uploads/downloads, but G start works.
To get around this, Garmin have now released TC V 3.2.2 which sorts this out. I had to do the reset again (Hold MODE whilst pressing ON/OFF button) to clear all the data off the 305 to get it working again, but with the v3.2.2, it now uploads/downloads fine again.
Hope this helps.
Posted by: Kevin | February 16, 2007 at 11:27 AM
hi
i have a forerunner 305 that locked up after a full battery charge after following tips on how to reset it the system now works great ie locates satellite very quickly and pace readout it very even but since the reset i cant send history from my 305 to my pc but i can send workouts from my pc to the 305.
The pc tells me the 305 is not recognized but still allows me to send workouts
any help would be appreciated
Posted by: steve partridge | April 27, 2007 at 12:43 PM
Hi all,
My Garmin/Forerunner 305 unit will not unlock with the Mode/Reset then power on fix.
I also tried the reset with external power applied.
Hope you have a solutions.
Posted by: Renate | June 04, 2007 at 07:34 AM