Hi, I have a broken Scanjet 3300C and I need schematics to repair it. thanks

What is wrong with it. Reason I ask, is, I have an HP scanner, and it fails to detect. I checked into this in HUGE detail, posted comments on the HP site (which is full of nasty comments for HP) and eventually, disected the thing, and threw it away. It would appear, there is a generic fault on HP USB scanning devices, which is of epidemic proportions. They just FAIL, and folowing that, will never work again. The USB hardware craps out. If that is what is happening with yours, save yourself a lot of time, you are 1 of 1000's of consumers with a faulty piece of kit. -------------> never buying HP equipment again ($25 per PHONE CALL support line!)

The CCD fails to light up and the computer will not detect it. The Power supply works fine with my 12 port 10base-T hub.

Yep. Will not detect. The light works though, right? Mine would light up,sound normal, power running fine, but NOTHING would make USB detect it. You have seemingly the same problem, welcome to the pending "class action law suit". Go top google, type hewlett packard scanner usb fails detect and click search. You will see what I mean by epidemic.

I have come across 2 faulty scanners recently One HP & one non HP with the same problem This may sound odd but try plugging the mains adaptor directly into its own mains socket and not into an extension lead , I spent some time checking this . there is no logical explanation , but its works !

The light does not come on. It looks like the thing isn't receiving power, even thought the power supply works (checked it with multimeter). I took the thing apart last night. I will buy a $20 one from CompUSA.