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

When turned on with no PC connected the lights come 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. It's 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

On Mon, 16 May 2005 19:25:06 -0400, John Knowles wrote:
We have a Laserjet II which we would like to maintain.

Also:
comp.sys.hp.hardware
comp.periphs.printers

Jonesy
--
| Marvin L Jones | jonz | W3DHJ | linux
| Gunnison, Colorado | @ | Jonesy | OS/2 __
| 7,703' -- 2,345m | config.com | DM68mn SK

Thanks, I have posted my question to these groups

"Allodoxaphobia" wrote in message
...
On Mon, 16 May 2005 19:25:06 -0400, John Knowles wrote:
We have a Laserjet II which we would like to maintain.

Also:
comp.sys.hp.hardware
comp.periphs.printers

Jonesy
--
| Marvin L Jones | jonz | W3DHJ | linux
| Gunnison, Colorado | @ | Jonesy | OS/2 __
| 7,703' -- 2,345m | config.com | DM68mn SK

I have a HP LaserJet II & a III. My II had the same symptoms you
describe and the problem turned out to be a small electrolytic
capacitor mounted on the print density card. This is the small card
above the toner cartridge with the slide switch.
I know this sounds strange but some of the interlock circuits feed
through this card.
In my case the capacitor was open and would not give any kick to my
meter.

Van Gardner

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

"John Knowles" wrote in message
.. .
We have a Laserjet II which we would like to maintain.

When turned on with no PC connected the lights come 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. It's 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