asked Nov 22, 2004 at 1:55pm
Unknown Printer


I have a problem with my HP LASERJET III. It displays an error saying "50 -Service" I have been told already that this means that I have to change my fuser. The problem is know that I can`t find repair instrctions for my secific printer:
Who can help me out ?? The Prod.-Nr. is: 33449AB
I don't know who told you that the fuser is bad. In reality, 50 errors are usually caused by a bad AC power module in that model. http://fixyourownprinter.com/fusersx.html
by moe on Nov 22, 2004 at 2:42pm Add comment
According to the error lists error 50 can mean a bad AC power supply or a bad fuser.
I think it can depend on if it's a 110V or a 240V version.
I have never seen a AC power supply go bad in the hundreds of laserjet III, 4 or 5's I've seen, here in Europe a 50 error is usually a bad Fuser. - Briank
The LJ 4 is a much like the LJ 3 as a Pinto is to a Lexus.
There are no similarities, save both are laserprinters and built by Hewlett-Packard.
Moe is correct that the "50" is usually casued by the AC Mod.
I believe he has a kit on this site.

by unknown on Dec 7, 2004 at 5:50am Add comment
The power supply is the reason of the failure 50 error code. In fact, the tyristor or the all command electronics of the tyristor response for that problems. See the single tyristor on the power supply module.

Good luck to all!

by rares2004 on Apr 19, 2005 at 1:15pm Add comment
I replaced the fuser & power supply in a HP LaserJet III that was giving a "50 Service" message. It still gives the "50 Service" code (both fuser & PS were from working printer) Is there anything else I can swap out that might be the problem?

Thanks, Jim
by unknown on Sep 13, 2005 at 12:11am Add comment
Check out the fuser lamp for open circuit witha multimeter. If its' like the LJ4 you can get a new lamp very cheaply, particularly if you get the OE Canon part. The last ones I got in UK for LJ4 were about £4
by unknown on Sep 13, 2005 at 7:22am Add comment