Printing problems with Designjet 70

[archenno]

For some time, suddenly (after years of good operation, with only a change of cartridges and printheads), every time I turn it on it print half the test page, stops for about a minute, ejects the sheet and start again, always printing half a page until I turn it off. When it is re-lit it is the same, it does not allow me to print anything else. The result is the same both by lighting it without any printing or with a printout already sent. The control panel does not report any errors. I also tried to change the printheads.

Thanks to anyone who can give me directions

[Valsimot]

Can you take a photo or scan of that page and post it here?

[archenno]

here's the picture: interrupted test print

[Valsimot]

That is calibration page it is used to align printheads for best print quality. The printer prints marks in all 4 colours and then light sensor reads those marks and aligns. That bottom right X means that alignment failed, there should be green mark instead of X if alignment went OK.

The main reason for alignment fail is a poor print quality of one or more printheads.

Not sure if it is because of the angle the page has been photographed but it seems that you have poor yellow V marks in the bottom row on the left. 

I would recommend you to clean printheads if that doesn't help you will need to replace the yellow printhead.

https://support.hp.com/us-en/product/HP-DSJ-t120-series/295935/document/c01704193/

The printer will print every time calibration page when turned ON until it will be calibrated.

[archenno]

Thank you very much for your answer, you have been very helpful!

In the original calibration print, yellow is present like other colors.

Now I have found that by pressing the X key on power up I can avoid printing the calibration page, then the designjet works normally. Since I get good prints, with all the colors saturated, including yellow, does not this mean that the heads are in good condition? Given their cost I would like to avoid replacing heads if not necessary.

I tried to clean the heads (even if they did not look dirty) without changes. Are there any other hypotheses?

[Valsimot · Accepted solution]

If the print quality is good for your bussiness you can continue to use the printer, only you will have to press red X every time printer is turned ON and start to align printheads.

If the colours are good then your printheads print good, then you might have defective or dirty line sensor ( that blue and yellow light that reads markings on alignment page), defective trailing cable ( white FFC that connect you carriage with main PCA), defective carriage or defective main PCA. But the cost of repair, if any of the above parts are defective, will be high.

I would stick with pressing red X, that is the cheapest solution to continue working with your printer.

[archenno]

I will certainly go forward with the solution you suggest.

Thanks again for the quick and comprehensive answers