P4014dn Pre Feed Sensor

[IcecreamLtDan]

So, customer brings this machine in for us to fix.  Upon power up and warm up, machine immediately presents a "13.20.00  Jam in tray 2" message when there is no paper jam present.  Using the manual sensor diagnostic tests, bit B set to 1.  This relates to the ps 102 tray 2 pre-feed sensor.  This sensor is normally blocked with a flag when there is no paper present, and it is blocked, but still shows a bit set at 1. 

Now, if I thump on the sensor assembly with my finger or other object, the bit will change to zero.  If I then go and run the machine, it will run a few pages, but eventually always ends up with the jam message with no jam present and the bit is set back to 1.  I have pulled the assembly out, a fun job  by the way, and cleaned the sensor, ensured everything is intact and moving freely and it seems fine.  I reinstalled the sensor and the machine ran a few pages and then showed the same symptoms.  Sometimes, if I switch the machine off and back on, the problem clears and I can run a few pages, other times, turning it off and back on does not clear the message. 

My conundrum is this, I cannot find this assembly in the parts catalog.  I've looked through it thoroughly and cannot locate it.  An internet search has also proven fruitless, other than I am not the only one who has searched for and failed to locate a replacement.  So, do I need to tell this customer, whose machine is still under warranty, that the part I need to fix it is not available.  I don't have a problem ordering the next highest assembly if needed but, it doesn't even show it in the catalog, nonetheless what assembly it would come with.  Anyone have a part number, or know what assembly the sensor is included with?

[SHThompson]

CB512-69056

LJ P4014N Unit 110V Bundle

If the whole unit is not orderable you might have to call HP support, one of the Care Pack options for that model was next business day exchange so HP should have them available.

I tried to find the part number for PS102, but had no success.

[IcecreamLtDan]

Hi and thanks for the response.  I will probably give HP a call about this after the holidays and see if I can order the part you specified.  I did try an experiment today and verified that the sensor assembly itself is bad.  I too  have had no luck finding either the PS102 photocell, nor any sort of higher level assembly that contains it.  It and two other photocells are mounted to a plastic framework that is its own separate assembly that mounts directly to the frame.  All 3 photocells are part of a wiring harness with a single plug as well as a 4th photocell that mounts to the frame with a screw through the board.

I removed the whole assembly from the machine, again, a truly fun project, and then reassembled the machine enough to get it to come on.  The assembly is a photocell sensor soldered to a board as opposed to the more common sensor with a plug on it.  I can physically press the sensor assembly with my finger and get the diagnostic bit to change.  I tried that with the other 3 sensors that are part of that assembly and did not get any change from them.

I had hoped that maybe it was just a cold solder joint or something.  I removed the wires from the board and cut and re-tinned the ends and re-soldered them back on.  I then re-soldered the photocell to the board.  This did not cure the problem.  I then de-soldered and swapped the photocell assembly with the one adjacent to it and the problem followed the photocell.  This tells me the photocell unit itself is indeed bad. 

Now if I can just get one to replace it with.  Unfortunately, all our spare parts machines were drmo'd prior to the end of the fiscal year and we haven't had any HP products come in that I can get parts from and probably won't for a while as the base is changing everything over to Xerox machines.

[SHThompson]

Hopefully hp will ship you that part number since it's the whole machine which will definitely fix your problem.

The description does not have ID in it so you might have to move the duplexer from the old one to the replacement.

You can get PS104 for that machine which is a plug in module so the question there would be is the photocell in that the same photocell you're seeing on the board.

Did you happen to take a picture of the assembly that you could post?

Also sometimes if you carefully examine an assembly you will find a part number molded into it or label on it and that part number can be ordered.

[IcecreamLtDan]

Good morning sir, thanks for your response, not entirely sure you're responding to me as I don't recall a conversation about the duplex unit, and it's actually not installed in the machine currently.  I will take a look and see if PS104 is the same style sensor or not.  Here are some pics I took of the sensor assembly.  I have tried to search for all the numbers that I see printed on the circuit board and come up empty.

[IcecreamLtDan]

Here's another view.  The sensor in question is the one that's in the middle of the plastic assembly.  It is PS 102, the other two are PS 103 and PS 106.  The one that's by itself is PS 108.  They are all hardwired to the same connector, which plugs into J 94.  They are easy enough to desolder and swap, which I did with PS 102 and PS 108, and the problem followed the sensor assembly so I swapped them back to original.  I'll take a look at PS 104 and see if it's the same type and can be ordered.  If so, that should resolve the issue.

[IcecreamLtDan]

So, I looked at PS 104 and unfortunately it's a different style photocell.  It's the more standard type that we're all used to where it's just the sensor with the connector that the wire harness plugs into.  I wish PS 102 was one of those, I have several in a drawer I keep on hand for just such a need.  I may look to see if there's some way that style photocell can be modified for use in this location, but I have my doubts.

[SHThompson]

The part number I provided is for a whole printer and if you look at the description of that printer it just refers to it as a n model and not a dn.

Since you have a dn machine it HP ships you one without a duplexer you will have to move it from the old machine to the new one.

I work for an authorized service provider and in this scenario for an in warranty machine I would have ordered a whole unit replacement.

[SHThompson]

Just got a spare minute to look at the picture on a PC, the sensor looks familiar, but I can't place wether or not I saw it in a P401X or some other machine. (hard to see the details on my Smartphone).

[SHThompson]

Did you look closely at the circuit board to see if there was a part number on it?

Does it look like RM1-4040? (your picture does not have a top view of the board)