I picked up an HP Officejet J6480 printer the other day, only because it had the duplexer and Ethernet (neither of which our home inkjet has)
It seemed to run OK, but soon after, the (woefully-short) AC cord parted company with the PSU's socket. When I plugged it back in again, the printer was unresponsive via the front-panel conrols, and the scan light was on (and flickering, I'm guessing at around 40Hz).
I've read about similar-sounding symptoms caused in HP printers following power outages, but of course it's all consumer-level advice suggesting that the machine be returned to HP for servicing.
So, does anyone have any familiarity with this fault (possibly on another HP printer, as they doundless share some common design elements)? The PSU voltages seem healthy still (+16VDC and +32VDC) and the LEDs above the Ethernet connector are on (I expect those are running at a much lower voltage, suggesting that some of the internal regulation is OK)
As it was a freebie I'm not really bothered if it's snafu, but on the other hand if it's a likely case of a simple part that's failed then I might pull it apart and attempt a fix.
cheers
Jules