Laserjet II "printer opwn" error

[John Knowles]

We have a Laserjet II which we would like to maintain.

Whwen turned on with no PC connected the lights come on on the front panel
and the display says the printer is doing a self check. After a few seconds
the lights go out and the display reads "12 printer open". At no time can
the fans or motors be heard. I tried opening the top, depressing the
microswitch which is normally activated by the longish plastic tab on the
cover, and powering on. I do not see a fuser lamp glow when I do this.

I took the DC Power supply (RGI-1394 (02)) apart and checked the
microswitch-OK.

I do not have +24V between pins 1 and 14 on J212.

I do have 169V on the large electrolytic capacitor which must mean there is
rectified mains voltage ready for use by the switchmode circuit.

This is as far as I wanted to go without a circuit diagram.

Can anyone suggest where I might find a service manual with schematics or
just a DC power supply schematic?

John Knowles
Montreal

 

[Silicon Sam]

I haven't remembered part numbers in a while, but you're sure this
isn't a IIp or IIIp? Reason I ask, is the 12 Printer Open is a common
failure to that printer.

Raymond

 

[jbuch]

We have a Laserjet II which we would like to maintain.

Whwen turned on with no PC connected the lights come on on the front panel
and the display says the printer is doing a self check. After a few seconds
the lights go out and the display reads "12 printer open". At no time can
the fans or motors be heard. I tried opening the top, depressing the
microswitch which is normally activated by the longish plastic tab on the
cover, and powering on. I do not see a fuser lamp glow when I do this.

From www.fixyourownprinter.com

Error 12 Printer Open no EP cartridge

* Check that the toner cartridge is installed.
* Check that the top cover is firmly closed.
* On HP II/IID/III/IIID printers this error is usually caused by a
bad DC power supply.
* On HP IIP/IIP+/IIIP printers the primary cause is the density
adjusting PCA. There is a slight possibility of it being a bad fan.
There is also a slight possibility of the tab on the fuser access door
above the MP tray breaking off and causing the error. If the fan starts
to run, quits and you notice a burning odor, the scanner motor has
failed and needs to be replaced. The problem can also be caused by a
defective drum shutter on the toner cartridge.
* On the 4/4M/4+/4M+ the tab on the top cover that actuates the
door interlock could be broken.

You say you have no +25 volt DC?

Google is your friend

Search terms "laserjet error 12 printer open"

Lots of hits.

Good luck

 

[John Knowles]

It's a II and not a IIP and now has a functioning 24V supply. I removed the
PC board and found a crack in the board caused, I think, by rough handling.
There were several broken traces which I repaired. All I need now is a new
separator pad!

Thanks for reponding

 

[ken smith]

John,
Why do you need a separation pad? I've never had any problems with those.
It's usually the paper feed roller that dries out. I can send you a
separation pad for free if you want.
Ken