I am having a similar problem:
HP Photosmart C3180 all-in-one printer.
Will print documents, but when I open Image Capture, I get an error message: No camera or scanner connected.
I already did the following:
shut down / unplugged the back of the mac
turned on/off printer
unplugged USB from back of mac and plugged it in again
deleted printer: system preferences print & scan > right clicked on the printer (listed on the left) > reset printing system > shut down the mac > restored the mac > added the c3180
What else can I do? I need to use my scanner, especially with tax season approaching!!
~using OS 10.7.5