Designjet t620 setup heads?

[D Hook]

I'm working on a Designjet T620 and it's calling for setup printheads to be installed. Not sure why. I did clear the EEROM just before I got the message. I've never seen setup heads for this model, usually just on the 5000 and 1000 series.

So took a quick look on Ebay but not sure these are correct. Anyone know? Not sure how these work since they don't make contact with the carriage except for the obvious front of the printhead slot.

https://www.ebay.com/itm/183031110309?hash=item2a9d811aa5:g:Z1kAAOSw7IFddiuk&amdata=enc%3AAQAIAAAA8DZWEd%2FxqP0it2SGVOqDJIU%2FWV7a8ZIUGWclMT%2FnKr2LwH9ROliObmEJ6Q7gBEnfYNt7fhF48feIyEY4nuer2SwMsiJ6AvEY6NQj18m39h1Rh0w3dcmlZBR9X4UaJyNzQIfLdRu%2BVVycEQCMOs5toYKUiEsOFAOrlIuJGYsLwcga8U7F%2FXPOFSzpYarFHomkbyklHVhweq0AlTF0O7X1WM%2FqduBQaEWa6iinrsmk4bq8SULcudP3Z8yEItKhOwtiho9IB6T19XWwpxZzH%2BToC2WWYKheJdjau8Rkdj9fMHLRtb3aiDtXtZCEIMIWv6hO3Q%3D%3D%7Ctkp%3ABk9SR6iW5diPYw

[Kiran Otter]

Re: Designjet t620 setup heads?

Yes, those are the correct setup heads, however, they are only for use on a NEW tube assembly. If the tube assembly already has ink in it, then I would just skip using the setup heads. There's no air to remove from the tube assembly.

What I've done when inadvertently prompted to do so, is just fold up a paper towel and lay it across the ink plenums, and close the carriage on it. This will hopefully avoid a ink leak and let you get past the message to install the setup heads.

Kiran

[D Hook]

Re: Designjet t620 setup heads?

Exactly what I did. And it worked great.

Other problems with the printer that I won't go into now but soon.

Thanks!

[D Hook]

Re: Designjet t620 setup heads?

Working on this printer a bit more. This is a printer I sold to a client about 4 years ago to replace a 5500 that was just too big for what he needed. He used this one for those 4 years and it worked good for him. He recently bought a T520 new off Amazon to replace this one because he wanted to upgrade. So this was a freebie, just to get it out of his way.

I knew the yellow/black printhead was needing to be replaced, according to the front panel error message. When I checked the printhead status through the front panel it said "replace" for the y/bl printhead. The other two (m/c and pk/g) registered their status as "OK". The previous owner said it was printing ok up until the point he got a message to replace the y/bl printhead so I'm assuming the other two printheads were working ok. I don't know for sure since I haven't been able to see it print anything since I got it.

So I put in a used but known-good y/b printhead and the printer started to go through it printhead replacement routine. All the ink cartridges are over 50% full, though a couple register as "expired". (My experience has been that expired ink still works ok once you've "confirm" you know the ink is expired but want to continue anyway.) Stage 1 (10 minutes) went ok. Stage two (5 minutes) went okay. Stage three (10 minutes) went ok up to about 1/2 way when it threw a dreaded 79:04 error. (*As a side note, having watched this process several time now, I think that stage 1 and stage 3 are the same. Stage 1 will bring the carriage to the placement where the carriage cover is able to be opened and ask you to open the cover and replace the printhead(s) but you only need to open the window and close it again to make it continue. The printer gets past this process on stage 1 but stops at that same place on stage 3, right after the carriage parks in the "replace printhead" placement on the printer.) I rebooted and went to the front panel menu to check the printhead status again and the y/b printhead had a status as "UNK". Also got the message on the front panel that the printhead replacement has not completed and to press OK to restart the replacement process.

I got the same results with the printer throwing the 79:04 error at the same place in the process. So I rebooted again, went to check the printhead status again and now all three printheads are throwing a "UNK" error message.

Went to the menu and reset the EEROM to see if that might get the printer to recognize the printheads but no luck. That's when I got the request for the setup printheads to be inserted. So I did what Kiran suggested to get past that but still have all three printheads registering as status "UNK". So I replaced the other two printheads with used printheads from a T1200 and still again got the "UNK" status message. Tried the printhead replacement process a couple more times and still stopped with the 79:04 error at the exact same point in the process. (I also tried shutting down, removing all printheads, ink cartridges and paper and reboot, then reinstall consumables when asked. Made no difference in the printhead status; still "UNK".

Now I'm on the verge of replacing all three printhead$ with new (expired) unopened and unused printheads but am wondering if I'm wasting money and if the "UNK" status message will now register as "OK" and let me get past the stage 3 stopping point. Was wondering if anyone else has run into this problem when replacing printheads and knows if replacing all three printheads with new/unused will solve this. And how the printer changes the status from OK to UNK and what triggers that.

Thanks for reading. Any help much appreciated.

Merry Christmas, Happy Holidays.

[Kiran Otter]

Re: Designjet t620 setup heads?

IMO you have to rule out the consumables before throwing parts at it. I would put all new (expired is ok) printheads in it and see what it does. And keep in mind that just because they're new doesn't mean they're good. I've witnessed scores more of bad HP inks and printheads in the last couple years than ever before. If the tube assembly has never been replaced you may have air in the tubes which will also cause a ph problem. They will function OK at first then start acting like they're starved for ink. If the tubes are not leaking at the printheads you can attempt to draw ink from them with a syringe but if there's any doubt about the tube assembly, I would replace it. A refurbished tube assembly from LPS is not that expensive.

Kiran

[D Hook]

Re: Designjet t620 setup heads?

Don't think it needs any parts, just the printheads. I think the "UNK" status is what's stopping it from completing the printhead replacement process. Was wondering what makes the printhead register as "UNK" instead of "OK". Won't know until I put in new printheads I guess. Was just wondering if anyone else has seen the "UNK" status and what triggers that status.

[D Hook]

Re: Designjet t620 setup heads?

Update: This isn't meant for you veteran techs, more for we less- experienced that visit here from time to time to get some help. This is long-ish but hopefully has some useful info.


Printhead install went well but took some time. Only hit a 79:04 error once after initial installation and while it was doing the Printhead Replacement procedure. Rebooted and started over by shutting down from the power switch on the back. Proceeded to another "Printhead Replacement Not Complete" error so started again. Step 1 took 15 minutes this time (usually only took 10 minutes), Step 2 took another 8 minutes, Step 3 took 5 minutes and Step 4 took another 5 minutes. Then it did a printhead alignment and an image quality printout. Looks good.

After it came to ready status I printed a couple demo prints from the front panel and they came out great. Checked the Printhead Status of each printhead and came up "OK" instead of "UNK".

Shut down and unplugged and pulled the formatter card out and changed the CMOS battery on the board, since it was probably original. Reinstalled and rebooted. All good.

Downloaded the driver for Win 7 64bit to my laptop and also the latest firmware and updated the firmware through the EWS system. Went good. There's a few steps the printer does on the firmware update that requires some patience. There's a couple times, after the download, the panel doesn't tell what's happening and there's a temptation to reboot manually but then continues on. Have to wait for the large percentage numbers to complete on the screen, then it's completed and will come to ready status. I was hoping the firmware update would cut down on the time it takes to get through the "Preparing Ink System" procedure from a cold boot and maybe it did a little but not much. It comes up quick when coming out of sleep mode and comes to ready state, as it should.

Checked system info and confirmed firmware update was now loaded.

Printed a test page for the laptop and a technical drawing and all went great. Just need to do a little cosmetic clean up, check the belt and the service station and it should be ready to go. Thanks to everyone that contributed.