The unit will not turn on. when I unplug it and replug it comes on but goes off immediately.

possible bad power transformer or unit is overheating

Unplug and replug everything, try a different socket, try a different extension cord/power strip (or with none). I have gone through my fair share of power strips and extension cords ruined by power surges. Repost with more specific information if none of this works (like what happens before it goes off; can u turn it back on immediately afterward or not?) If you see a yellow light (ps3) or red ring (xbox 360) before it goes off your console needs fixing.

Are you using the garmin power cord or are you using an aftermarket cord? Some after market cords have usb plugs that although they plug right in to the power port on the unit, they tell the unit that you are updating the database. The unit displays only a picture of a computer connected to the unit and that's all it will do. Their is a way around this. Simply wait until the unit displays the about photo of the computer attached and then unplug the power cord from the unit. After the screen clears immediately replug in the power chord. This must be done quickly before anything appears on the screen. If you're too slow, simply repeat this step until you manage to replug the unit before anthing appears on the screen. Once plugged in as about the unit will operate normally on the external power source until you either turn it off or unplug it. Simple repeat above when ready to resume use.

Unplug replug about an hour later,if the same problem than ur backlight video board it dead.Need it replaced.

Bad IHVT ( transformer ) = Part # 239111 use original only, no cheap subs !...............T.

Turn off printer and unplug it from power supply.
Check ADF if it appears to be damaged ( open the top portion so that you can check the mechanisms ) unplug the ADF cable from back of scanner and replug it, replug power cable, turn it on and try scanning using adf again.

My system seems to be locked in stand-by. When I unplug and replug the red power light comes on, but bwhren pressed just starts blinking like in stand-by. Help

www.pioneerservice.com check C258 video assy.