I have had a Topoeak Panoram V12 wireless computer since July, 2014. Three days ago, it went blank and I lost any accumulated data. I reset the circumference. The only data that is accurate is the

It sounds like your computer reset itself. This may be due to a sticky button, as most computers are installed at the same place where folks have their aero bottles. Some of the nice sticky glucose liquid runs onto the computer face when you drink, gumming up the buttons. Try wiping your computer face with a hot damp (not dripping wet) rag. If this is the problem, the hot water should remove the sticky stuff on your buttons and allow your computer to work properly.

Here you go:
www.veloonline.com/data/afile/insrukciya-o-rimeneniyu-59.pdf

You may have to re-install the battery and start over.

http://topeak.com/products/Computers/PanoramV12WideScreenWireless

Downloads in various languages on right.

While off the bike, try spinning the wheel (with the bike supported with the wheel in the air) and move the wheel sensor closer. Be careful not to get your fingers stuck in the spokes. Make sure the sensor lines up correctly. If this doesn't work you may have a defective unit.

there's just one button on this unit if i recall. so just get to the screen where it shows the trip meter, and press and hold the button until it resets.

try this site www.topeak.com/Service_and_Tech/Downloads

You can download the manual here: www.topeak.com/mediafiles/assets/341/file/1
By performing a reset and setup under section A. of the manual you can select 24 or 12hr time.

Just call/contact Topeak. In many cases they will send you the part as a warranty item at no cost to you. If not they can sell you what you need.

Download the manual from Topeak's website:
http://www.topeak.com/Service_and_Tech/Downloads