t2500 printhead mysteries

**tmw** · 02-02-2021

I'll start at the beginning, please try & bear with me. Called with printhead error / reseat printhead message. Brought a new printhead. When I arrived the ph was out & sitting on top of machine. I wanted to perform the replacement properly, so I put it back in the carriage so I could initiate the procedure through the panel. It went through the process like it was installing a new head. It got to the end & started printing alignment sheets & came to ready like nothing happened. I printed several pages successfully but considering the client, I didn't know if I should leave it in case it errored again.

I tried to install the new ph 3 times each saying the install couldn't complete. I took it out and it looked like one of the chambers wouldn't fill with ink. I didn't want to leave it like that, so I put in the original and it came up again & printed. so I left hoping for the best. A day or two later they called back & said it had the ph error come back.

I came back with another new ph and ready to run all the diagnostics having to do with the problem. After fighting with it to enter the diag mode, I eventually got through the ink tests, service station, pump, & carriage tests. All of them told me it was ok. However when it came back from the carriage test, it said the ph couldn't complete installation. Well maybe there is a problem with it this time. I went to install the new new printhead and it did exactly as before with the old new ph.

Even though it didn't look like there were air bubbles in the tubes (and the machine told me so ) I thought I would try a purge. I put the old ph in to try & do it like the manual said and it came up to ready again. I was going to try the purge anyway, then it had me me installing all the ink carts it thought it was going to run out of beforehand. I got to one they didn't have & couldn't continue. So I exited out. Every time I turned the machine back on it went back to where I left off. ( As a sidelight, I had a heck of a time getting into diags at first. After every test I had to exit & restart it. Now it's starting in diags by itself. I thought it automatically exited when the machine was powered down. )

Anyway, later they found another grey hiding somewhere, put it in and it started working. None of this makes any sense to me. I had the manual, but it makes no mention of eventualities or contingencies. I would like to know if any of the experts have any insights that would illuminate the situation. As usual I thank you for your input.

**Phil B.** · 02-02-2021

Originally Posted by tmw

I'll start at the beginning, please try & bear with me. Called with printhead error / reseat printhead message. Brought a new printhead. When I arrived the ph was out & sitting on top of machine. I wanted to perform the replacement properly, so I put it back in the carriage so I could initiate the procedure through the panel. It went through the process like it was installing a new head. It got to the end & started printing alignment sheets & came to ready like nothing happened. I printed several pages successfully but considering the client, I didn't know if I should leave it in case it errored again.

I tried to install the new ph 3 times each saying the install couldn't complete. I took it out and it looked like one of the chambers wouldn't fill with ink. I didn't want to leave it like that, so I put in the original and it came up again & printed. so I left hoping for the best. A day or two later they called back & said it had the ph error come back.

I came back with another new ph and ready to run all the diagnostics having to do with the problem. After fighting with it to enter the diag mode, I eventually got through the ink tests, service station, pump, & carriage tests. All of them told me it was ok. However when it came back from the carriage test, it said the ph couldn't complete installation. Well maybe there is a problem with it this time. I went to install the new new printhead and it did exactly as before with the old new ph.

Even though it didn't look like there were air bubbles in the tubes (and the machine told me so ) I thought I would try a purge. I put the old ph in to try & do it like the manual said and it came up to ready again. I was going to try the purge anyway, then it had me me installing all the ink carts it thought it was going to run out of beforehand. I got to one they didn't have & couldn't continue. So I exited out. Every time I turned the machine back on it went back to where I left off. ( As a sidelight, I had a heck of a time getting into diags at first. After every test I had to exit & restart it. Now it's starting in diags by itself. I thought it automatically exited when the machine was powered down. )

Anyway, later they found another grey hiding somewhere, put it in and it started working. None of this makes any sense to me. I had the manual, but it makes no mention of eventualities or contingencies. I would like to know if any of the experts have any insights that would illuminate the situation. As usual I thank you for your input.

this is a known problem with these units.

it doesn't help that they left the printhead out.

are they running genuine OEM inks?

when you were swapping PH's was the unit powered down?

i do believe you have to exit from diags before powering down

**Kiran Otter** · 02-02-2021

How full were the ink cartridges to begin with? In my experience, the replace printhead dance goes around and around unless you start it with full ink cartridges. It doesn't tell you it's either out of ink or too low on ink to complete the printhead installation. I don't know if this has been corrected in newer firmware.

Also, it's a really bad idea to attempt to purge the ink tubes if they have ink in them and you don't have the setup printheads. I'm surprised it let you do it with a printhead installed. That option is only for when you replace the ink tubes assembly.

Glad to hear you got it working though. I seriously dislike these models with the unified printhead.

Kiran

**blackcat4866** · 02-02-2021

IIRC the last new printhead I installed came with new ink cartridges in the same package, and the machine would not let me proceed until I had changed out all the ink cartridges. Maybe a firmware update? I left the partials with the customer, in the hopes that they could use up the remainder at the next ink change.

The weird thing about that call was, I also found the printhead out on the counter upon arrival. Upon examination I noticed it was leaking cyan all over the paper path, and the prints left lying about. There is a mylar self-adhesive seal on the top of the printhead that was punctured. So I did not attempt to re-install that printhead. =^..^=

**tmw** · 02-03-2021

Thanks for all your replies so far. The inks were all oem, but one of them was saying it was expired by a few months. It stuck out in my mind, but it didn't seem to be a big deal since you can prompt past it & I don't know what hp expects you to do if you don't blow through all your ink in time. So I'm going back with a fresh new set of inks & whatever else I had with me and hope for the best. I still wonder, though, why the one chamber in the ph didn't look like it filled.

Thanks, you guys are a great resource.

**Kiran Otter** · 02-03-2021

The only thing that 'expires', is the warranty. I've used heads and inks that were expired by 10 years and they work just fine, but they have no warranty if they don't.

Make sure you moisten the plenums on the ends of the tube assembly before installing the printhead. This helps to make closing the latch easier. It should be noted in the instructions with the printhead.

c04227333.jpg

https://support.hp.com/gb-en/document/c03797032

Kiran

**tmw** · 02-18-2021

Final disposition if anyone wants to know. HP recommended replacing either the primer assy or the iss svs side going by my description. I just replaced both so I wouldn't have to take it apart twice. Even though they said I could use the print head that wouldn't complete installation, it wouldn't take it. After I got a brand new p h, it took it & completed the installation procedure. Thank goodness. Now I'm stuck with printheads that I can't do anything with. Is it worth the risk trying to use them again telling the machine they're used ? Thanks to all your replies.