HP Laserjet 5P - help diagnose error

[Nathan Mates]

I own a Laserjet 5P, roughly 18K pages printed, and it has recently
started refusing to print. This has been verified with the "demo"
page, so I doubt that it is something to do with my host PC. I have a
Postscript SIMM, as well as some expanded memory SIMMs, but this still
happens with them removed.

Short summary of problem: when it attempts to print, about a second
after the motors start to whir, the second green light and the three
orange ones light up. The printer is then unresponsive until I
powercycle it.

Longer description: with the left side panel removed, there are 5
LEDs on the top, and one on the bottom-front-left (near the IR port).
When I turn the printer on, they all blink on, then the top 5 go in
sequence twice. Finally, the first green (identified with a '1' on the
metal brace above the SIMM slots, has a rounded-U icon) is solid. If I
hold down the purple button to get a demo (the button right of LED
#1), then the first LED blinks for a few seconds, the motor starts to
whir, then it goes into this failure state. At this point, LEDs 2 thru
5 are solid, and only the power button "fixes" it. LED 2 is green, and
has an icon with a piece of paper and a down-arrow. LED 3 is orange,
and is Paper Source 2. LED 4 is orange and paper source 1. LED 5 is
orange, and is the jam icon.

Any suggestions on how to interpret these lights? [I tried google,
and it mainly mentioned numeric failure codes, with values too high to
be binary-interpretations of bits 2..5 on.] Any suggestions on how to
address this? Is this something that would require a trained
technician? And, if so, any recommendations on repair shops near
Santa Monica, CA? Or, are there some good websites I've missed if this
can be manually addressed by someone capable of self-assembling a PC?

Thanks in advance for any suggestions.

Nathan Mates

 

[ato_zee]

Any suggestions on how to interpret these lights? [I tried google,
and it mainly mentioned numeric failure codes

Maybe the fuser isn't getting hot. You need some way of seeing the
lamp, should come on for about 20 secs at power up, then for a few
secs per minute. There are a few websites with the HP take apart
manuals, with basic schematics, in PDF format. If the fuser isn't
heating, component level diagnosis isn't too difficult, usually there
is an isolating opto-coupler driving a power triac (a solid state
relay) in the lamp circuit. There is a thermistor in the fuser assy,
and a few sensors forming a protection system. You focus on
whether the around 10mA drive to the opto-coupler is there.

 

[Dani]

Any suggestions on how to interpret these lights? [I tried google,
and it mainly mentioned numeric failure codes

Maybe the fuser isn't getting hot. You need some way of seeing the
lamp, should come on for about 20 secs at power up, then for a few
secs per minute. There are a few websites with the HP take apart
manuals, with basic schematics, in PDF format. If the fuser isn't
heating, component level diagnosis isn't too difficult, usually there
is an isolating opto-coupler driving a power triac (a solid state
relay) in the lamp circuit. There is a thermistor in the fuser assy,
and a few sensors forming a protection system. You focus on
whether the around 10mA drive to the opto-coupler is there.

It would be a bit difficult to see the fuser light up since there is no
light in it. It's instant-on ceramic heater technology. Good bit of
razzle dazzle with the techno speak. A non-tech would be totally fooled
by it.

What the heck are you doing on this ng? Most of the people responding
here (like Nathan) aren't techs, they just happen to own a printer,
read a lot of posts, but have no clue how they work. They think they
are helping, but they'll cost you money in the long run. I can't
believe you were on Google and didn't see http://fixyourownprinter.com
Real techs there and a searchable data base with close to 100,000 posts
on everything printer related. Pop in your model number in the box on
the main page and you'll find your answer in minutes. Need a part or a
video to show how to install it, you can get one there as well. Service
manuals are also available for free download.