Li@USCN.BITNET (LI Jialin, UGA Physics) (02/21/90)
I have a LaserJet+(call it LJ No.1) needed a new fusing roller, so I
bought one from HP and replaced it myself. However it does not work. I
than took the whole thing(everything on fig.A) off, put it on another
LaserJet+(call it LJ No.2), it worked. Place it back to LJ No.1, still
wouldn't work. After a while I remembered that when error #50 first time
come up on LJ No.1 was because the connection of fusing bulb was open
(but after I connect it, the error #50 keeped coming up anyway). I did
waite 7 min before every power up, and did reset the AC Circuit Break
on the AC power supply.
While tring to find out why, I unintentionally reproduced the err #50
on LJ No.2, and the reason is the same: disconnect the AC power supply
to fusing bulb. Here is how I did it:
============================================================================
LaserJet+ No.2, works fine
AC thermo-protector AC (Note:
| [O] [OO] thermistor | thermo-
| .----------------------------------------------------. | protector
| : ___________________________________________ : | wired in
|-------|___________________________________________|------| seires w/
: fusing bulb : fusing
`----------------------------------------------------' bulb)
fusing roller
fig.A
=============================================================================
Power off, disconnect one side of the fusing bulb
AC thermo-protector AC
| [O] [OO] thermistor |
| .-----------------------------------------------------. |
| : ___________________________________________ : |
|----\ \-|___________________________________________|------|
: fusing bulb :
`-----------------------------------------------------'
fusing roller
Turn power on, error #50.
fig.B
============================================================================
Power off, reconnect it (as fig.A), wait more than 7min, power on. It
passed self test, and waited for 90sec, error message #50.
Now I have both printers dead and need anyone's help badly.
Thanks for any help in advance.
Jialinhenry@utzoo.uucp (Henry Spencer) (02/22/90)
In article <900221021008311.AOCJ@205FE.USCN.UGA.EDU> Li@USCN.BITNET (LI Jialin, UGA Physics) writes: > Power off, reconnect it (as fig.A), wait more than 7min, power on. It > passed self test, and waited for 90sec, error message #50. > > Now I have both printers dead and need anyone's help badly. Sounds like you've blown one of the boards that runs the fusing assembly. The only time we've had an error 50, one of those was bad. There are two little boards under the big plastic housing to the left of the fusing assembly. (Dismantle with power off and line cord unplugged! The main AC feed to the printer also runs around in there.) We fixed our error 50 by replacing the top one. If you have the service manual, there are some procedures in there for troubleshooting an error 50... but they quickly boil down to "replace boards until it works". -- "The N in NFS stands for Not, | Henry Spencer at U of Toronto Zoology or Need, or perhaps Nightmare"| uunet!attcan!utzoo!henry henry@zoo.toronto.edu
jans@tekgvs.LABS.TEK.COM (Jan Steinman) (02/22/90)
<henry@utzoo.uucp (Henry Spencer)> <"The N in NFS stands for Not, or Need, or perhaps Nightmare"> Around here, it stands for "No", and the "S" stands for "Security". The meaning of the "F" is left to the reader's imagination. Jan Steinman - N7JDB Tektronix Electronic Systems Laboratory Box 500, MS 50-370, Beaverton, OR 97077 (w)503/627-5881 (h)503/657-7703