Laserjet 1100 Error - Displays all 3 lights on - Sorted

Hmmm, an 1100 with all lights on means that you have a ROM/RAM error. Either the printer thinks that the ROM is corrupted or that an error has been found in RAM. The steps to correct this condition is as follows:
1. cycle power on the printer.
2. unplug the printer, remove optional memory, and test.
3. Replace formatter board.

A Laser Unit error would typically only have the middle light illuminated.

The  RAM/ROM was what I first went for then the main board then I found on the HP site that there is a secondary level of codes revieled by holding the go button down after you get 3 lights this pointed to the leaser unit.
Peter

Well, I don't know what to tell you. The error code meanings that I reported to you above are straight from the service manual, and that is when holding down the Go button. Please include a URL for the information you found because it contradicts the service manual, and I would like to review the information for myself.

Yes, I followed the service manual first then just happened to try the HP site which has never helped me before. please try this url, if it fails come back to me and I'll walk through it.
Regards
Peter
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=bpl05870&locale=en_US&taskId=110&prodSeriesId=25470&prodTypeId=18972

Sorry having re-read your last comment perhaps I should clarify that the initial 3 lights on indicated a fatal error which I misunderstood as a ROM/RAM error not realising that there was a second level of diagnostic code (via the go button) which brought up just the go light.  Its the first time I've really worked on a 1100, now having stripped and rebulit 2 completely I have no worries about them, pitty about the feed system though.
I originally had more detail on my question but having cured it I tried to remove the question but couldn't so I just edited it.