asked Jan 8, 2001 at 1:18pm
Hp HP LaserJet 4P

Replace LJ 4P Fuse?

The office power flashed off for about half
a second. We use a surge protector on the printer
and computer; the computer seems to work fine but
the printer no longer has any power, no lights,
no nothing. My first guess is that its fuse should
be replaced, but I have no idea how to do this. This
is an HP LaserJet 4P, about 7 years old, not worth
paying for a repair but I can't believe that there's
no simple way to replace its fuse. The user manual
is silent on the subject, nor have I found anything
on the web. Any advice or direction appreciated. TIA.
the printer has an internal fuse
it is located on the logic board on the underside
you will need to remove all the covers and remove the fuser unit..
then u will see on the left hand side of the printer there is another board.
remove this!!
now turn the printer over (upside down)
and remove the screws
you will also notice some screws holding it from the side
remove these as well
you sould now be able to remove the main board!!!
of the paper sensor that just sits in place as you remove it

the fuse is on the main board just after the mains supply

good luck andy

ps i know my stuff because i am a laser printer enginner in the uk

best wishes

by unknown on Jan 8, 2001 at 3:15pm Add comment
Thanks, Andy, for that description. I fear that I
might not be able to reassemble the thing. But
even if I can do that, and assuming the fuse is the
problem, how easily I can obtain a replacement fuse?
I wonder how much Moe would charge for one, and
how quickly I could get it. Or is this the sort of
fuse I can find in my local hardware store?
PS: Shouldn't HP be nominated for a bad design
by unknown on Jan 8, 2001 at 3:52pm Add comment
My 4MP jammed, and after I removed the paper, all pages are a uniform gray.Or mostly uniform. Some are almost clean, and in any case there is some horizontal striping.I gather they may be a damaged cartridge or spilled toner within.True? How do I get down to the fuser/etc to clean it? Is there a worthwhile service TFM available?
by unknown on Feb 16, 2001 at 6:39pm Add comment
The only thing I can associate with a paper jam and your subsequent problem is that you might have dislodged the charge transfer roller. Make sure you don't touch the surface of the roller when you snap it back in place, only the metal parts. Only other thing would be the toner cartridge. Fuser has nothing to do with the problem. If the fuser had excess toner on it, it would gradually clear up as the toner transferred to the paper. No matter what anyone tells you, a bad charge transfer roller will not cause this problem.
by moe on Feb 16, 2001 at 9:29pm Add comment