DesignJet 5500 - Check printhead path (2)

[brianallen]

HP DesignJet 5500 60" UV

Sometimes it turns on fine and starts a printhead calibration cycle, getting a large way through it then giving the error: "Switch power off / Check printhead path (2)"

Sometimes it won't turn on (initialize) and gives the same error while coming out of the left most area.

Sometimes it gives the error while coming out of the right most area.

When the head assembly moves, it seems a bit jittery.  I have another 5500, and that one seems to move more fluidly.  I cleaned both rails and re-oiled them, first applying a small amount of WD40 to a rag.  No effect.

Since it doesn't error at a specific spot, and sometimes gets further, and because it's jittery, I'm thinking it is tripping an error because the belt and head carriage isn't moving as it is supposed to.

Perhaps the belt needs to be replaced.  I'm thinking that wouldn't cause it to be jittery, because although the belt is old, the groves aren't worn and falling off.

Perhaps it's the motor that drives the belt.

What do you think is causing it, and how would you go about fixing it?

Video showing error when it moves head carriage out of cleaning bay : https://www.youtube.com/watch?v=jf88y_N_B_g

Video showing error when it moves head carriage out of left side, and close up of belt & head assembly acting a bit jitterry: https://www.youtube.com/watch?v=W6bFvQaD7vg

Video showing maintenance cartridge moving during initilization, to me doesn't seem to be acting up: https://www.youtube.com/watch?v=uEr79XljWsg

Video showing a close up of the belt, with me squeezing it to show how it reacts, and how it moves when I manually pull it (not very smooth): https://www.youtube.com/watch?v=87oM3tLN0XA

[Mikeg81]

Hi,

Try to apply oil instead of WD40.

Here is the part number of what is recommended 6040-0855.

I hope that helps.

Best regards

Mike G

[D Hook]

Mike is correct.  WD40 isn't too good for lubricating the rails.  Tends to gum up the works.  You might want to wipe it off good and try a synthetic oil instead.  I've used both the HP oil that comes in the maintenance kit and also Triflow lubricant that you can buy at most hardware stores.  Both are synthetic.  Have had good results with both. 

As for the error, you can try this:

Go to the front panel and push "Acess Printheads".  Then, once the carriage has moved to the left, lift the cover.  (Note:  If you have the safety switch defeated with a small piece of paper, you'll want to remove the paper so the printer knows the cover is open.  Otherwise, the carriage may move unexpectedly.  Very painful if you have fingers in the way.) 

Shine a flashlight into where the carriage parks on the right hand side and see if there is debris on or around the motor spindle.  Usually, when the belt starts to go, it will leave shreds of itself wrapped or imbedded around the motor spindle.  This will throw that same error.  If there is debris there, you'll need to change the belt very soon.  You can try to clean off the debris from the spindle and it should help with the error but it will happen again soon after as the belt continues to deteriorate.

I believe what happens is the debris changes the diameter of the motor drive spindle, moving the carriage furthur than the encoder strip says it should so it throws the error.  Or the belt is bad enough that it's slipping on the motor spindle and the carriage isn't in the location it should be on the endcoder strip, again throwing the error.

Either way, you'll probably be needing a belt change.  Not too hard to do.  Very good instructions on this forum, especially from David Zuts, who knows these machines inside and out, as well as other contributors who've kindly shared their knowledge.

Good luck with it!  Please post back what you find so others will benefit from your experience.

[davidzuts]

As the others have said you need to remove the wd40 (worst lubricant for printers) and lay down a small amount of synthetic oil. By your description I am 99% sure the belt needs to be replaced. Just google the service manual for the dj5000 since the belt replacement is the same and the manual for that printer is readily available on the net for no charge. I would also advise you order a carriage height adjust tool at the same time as you will need it to finish the belt installation.

[Frenchman]

Hello Sir/Ma'am.

     I have seen this problem on numerous occasions whether it stops midway on power up or stops wile the carraige is in fast motion left or right. Just stops for no apparent reason.  All of these problems, in my opinion was leading to the main power supply not being able to keep up the demand. Long story short, I removed the Power Supply and began testing the individual caps in the PWM circuit. Sure enough found, using a HUNTRON 2000, 2 caps flatter than a pancake.  One of my customers wanted to bet me $100.00 that 2 caps couldn't be causing all this trouble. I told him I didn't want to take his money. Upon replacing the faulty caps, the plotter powered up as it was designed without any further problems.

    Now I bet you wnat to know which caps to change.

Warning: If you are a PARTS CHANGER, I CAN'T HELP YOU. HOWEVER IF YOU ARE A QUALIFIED ELCTRONICS TECH GET IN TOUCH WITH ME THROUGH THIS FORUM AND I'LL HELP YOU OUT.

DRFRENCH

[davidzuts]

Have to disagree with your post.  I am a designjet technician for over 20 years.  I have worked on over 100 designjet 5000 series plotters with the check printhead path 2 error and have been able to solve all of them and not one of them was caused by the power supply.  My best estimate is 75% of them were caused by a bad carriage belt.  Maybe 20% due to dry rails and the remaining 5% due to other issues such as bad carriage motor, issues with the tube assembly or even bad carriage bushings.  You may have solved one plotter's issue with an extemely rare problem and I would not recommend others trying to repair a power supply to fix this issue, since 99% of the time the issue is something else.

[Frenchman]

Hello Professor.

   How bout I've been working on the Designjets since I got my A+ Certification back in 1993 when they were called PEN PLOTTERS.  Your free to disagree with me, but I have personally repaired 5 HP 5000/5500 Power Supplies that were causing all sorts of squirelly problems and not just "CHECK CARRAIGE PATH", though I picked that one as it had a lot of entries.

   I will not disagree that a good portion of "CHECK CARRAIGE PATH", is generally caused by the belt and or gummed up raiis.  But I will also tell you that I have repaired numerous plotter power supplies and not just on the 5000/5500. I have also repaired those on the 750c and the 1050c.

   So in closing, I will say that a percentage of technicians are "PARTS CHANGERS", and then you have the genuine techs that really dig in the books but don't find the answers, but they don't give up easily.  Personally, I don't expect the average technician to repair power supplies and that's why I said I wouldn't give up the info to any wan-a-be tech for fear they may have just enough information to make them dangerous... Have a nice day Professor... FRENCHMAN, CZB125

[davidzuts]

Most issues with the power supply on the 5000 series have to do with the 12V line that feeds the hard disk.  I have probably encountered maybe half dozen over the years  If you have information on repair of those power supplies I would be glad to receive it.  You can send me a private email on this site.

[Frenchman]

Hello again Professor.

    Before I give you this info on the 5000/5500 Plotter Power Supplies, I'd like to know if , in fact, you are an electronics tech or at least worked on repairing electronics and maybe familiar with "O" Scopes and maybe the "Huntron Tracker 2000" and do repair electronics.  And if so, I'll be glad to share the info with you.

    Afraid I'm I not familiar with sending "Private Emails" on this site, please clue in. FRENCHMAN

[davidzuts]

I am sending you a private message and you can respond to it.  Look for the mail icon next to the area where you log in.