Designjet 1055cm problem

[cscce]

I have a Designjet 1055cm with 2 problems. It says that the magenta printhead is faulty. It's a new printhead. Replaced it with another new printhead - still indicates faulty.
The other problem is that at power up it says that the paper is loaded incorrectly (but it's not). Remove and reload paper clears the error but it comes back the next time the printer is turned on.
System Electronics test passed.
Drop detector test passed.
I'm thinking maybe a board has gone bad. I have a second machine that is retired that I can use for parts. It hasn't been used for 4 years so I wouldn't trust the ink system.

Thanks in advance.

[theengel]

On some of these machines, printheads are tied together... I don't remember which ones. Kiran will probably clarify. Anyway, sometimes one bad printhead will throw off another good printhead. Soooo, did you replace all printheads or just the magenta?

If that doesn't work, I would think about replacing the carriage & trailing cables. You could start by replacing the carriage board and/or the flex cables, but I find it's easier dealing with a customer when you go straight for the jugular rather than leading up to the jugular and then going for that in the end anyway.

[cscce]

On some of these machines, printheads are tied together... I don't remember which ones. Kiran will probably clarify. Anyway, sometimes one bad printhead will throw off another good printhead. Soooo, did you replace all printheads or just the magenta?

If that doesn't work, I would think about replacing the carriage & trailing cables. You could start by replacing the carriage board and/or the flex cables, but I find it's easier dealing with a customer when you go straight for the jugular rather than leading up to the jugular and then going for that in the end anyway.

Thanks! I will swap out all printheads today.

[Kiran Otter]

Yes, one printhead can cause another to erroneously report being faulty. Plus it's not entirely unlikely to have two bad print heads even if one is new. It happens.

Look for air in the ink tubes in the back where they come from the ink cartridges. If you see air, you should plan on replacing the tube assembly. If no ink is getting to the print heads it ruins them, so you should start with a tube assembly before feeding it any more print heads.

I would avoid dissembling the trailing cable from the carriage if you can help it. It's likely you won't be able to reuse the trailing cable because the ends are dried out. Even when I replace the belt, I don't touch the trailing cable on these printers. Do make sure the flex cables (contacts that mate to the print heads) are clean. Just use a damp paper towel or coffee filter.. no alcohol.

Turn the printer off, remove all 4 heads, and then start it up.. then start the printhead replacement and insert each print head by itself and see what the front panel says. If you insert the magenta by itself and it says that it's faulty, then it's likely just a bad print head. If it's OK, and you insert another printhead, and now the first one says it's faulty.. then the one you just put in is likely bad even if it says it's OK. It also helps to wiggle the printheads until the status stays OK.

As far as the paper being misloaded on startup.. that could be a line sensor problem, or a carriage position issue. With the printer off, if you remove the print head cleaners, and push the tray all the way in, you can get at the bottom of the carriage. Make sure the white line sensor area is clean. Also while you're at it clean the drop detect sensor; twist a damp paper towel and shove it into the opening and work it around until it comes out clean. It also could be an issue with the rollers gripping the media. The edge of the media should just be visible at the rollers when idle. If it's advanced at all, on startup it thinks the paper is misloaded. With the age of these machines, that's a problem I'd probably just live with.

Kiran

[cscce]

Many thanks for the info. I checked this morning and, not surprisingly, there's air in 3 of the ink lines so an new tube system will be installed.

Mike