Recently my flatbed scanner — Microtek ScanMaker i700 — has developed a problem: it doesn't shut off after pressing the off button. When I turn it off, the scanner lights stay on and it "power cycles" itself as if for initial set up. After sitting idle for a few minutes, it repeats the power cycle. (So the scanner can't be used it this state -- it's different than when the power switch is "on.")
Unplugging the USB cord has no effect. Only unplugging the power supply turns it off completely. But if I plug the power supply back in, the scanner cycles again (even though the button is "off").
What's the likely cause? A defective power supply, a defective switch, or something else?
The scanner is old (circa 2004) and no longer supported, so repair is unlikely, but I thought I'd ask the forum members their opinions before I try searching for a new power supply.