Mysterious disappearing non-clogging related (?) banding issues on iP4200

[The Hat]

If you’re happy to continue to print in that way then that will work but in the end you’ll have to invest in a new print head if you want to get better prints, that’s the bottom line I’m afraid, sorry...

 

[elenhil]

I still don't quite get what's going on to understand what exactly am I loosing in print quality - colour intensity or resolution?

 

[PeterBJ]

Neither do I, but clearly the colour intensity is lower than it should be. Maybe the print head expert @Łukasz can explain what is going on?

You cannot rule out that the table of printing modes in the service manual is in error or is incomplete. Errors in some Canon service manuals do exist.

If you want to print the extended nozzle check (service test print) from service mode, then please read the first post of this thread, as there is an error to service mode procedures in the iP4200 service manual.

 

[elenhil]

Well, here's the service test print, if that's of any help.
.

As I've said, increasing colour intensity in print options solved the issue with regular plain paper prints. High-quality prints on photo paper show no signs of insufficient cyan intensity at all.

 

[PeterBJ]

Yes the service test print clearly shows that the print head has an electronic defect in both regular and light cyan nozzle sets. The service test print gives a much more detailed image of the nozzles than the regular nozzle check from user mode, as all the colours are printed as grids like the PGBK in the regular nozzle check. The grids are small, so good light and a magnifer might be a good help in studying them. The yellow nozzles are printed on top of cyan to make them more visible on white paper. It is also seen in the yellow nozzle check that there is a problem with cyan.

Here is a crop of the service test print from the service manual. It is seen that all colours plus pigment black should show regular grids.

There is a small chance that removing the print head and cleaning the contact pads on the back of the print head and the contact springs in the print head carriage with a rag moistened with an electronics cleaner or isopropyl alcohol will clear the error. If this doesn't help, then only a new print head might help.

There is a risk that a defective Canon print head can damage the logic board, and a damaged logic board can damage a new print head, so replacing a Canon print head is a gamble, and I cannot tell the odds for success.

To remove the print head for cleaning open the printer as if you would change a cartridge. When the print head is at the centre, pull the power cord with out using the printer's on/off switch. You can now remove the cartridges and the print head.

 

[palombian]

If you’re happy to continue to print in that way then that will work but in the end you’ll have to invest in a new print head if you want to get better prints, that’s the bottom line I’m afraid, sorry...

To be comfortable when working with second hand printers (and 3th party ink) you must try to build your own stock of spare parts/printers.
Make a list of all printers using the same printhead as yours and check 2nd hand sites regularly.
You can find barely used printers for a fraction of the new price, and certainly much cheaper than a new printhead.

 

[martin0reg]

To be comfortable when working with second hand printers (and 3th party ink) you must try to build your own stock of spare parts/printers.

To stay comfortable when living - don't do that
http://www.printerknowledge.com/threads/you-know-youre-a-printer-addict-when.1401/

 

[Łukasz]

Tested that and found out that Duplex Printing is the culprit. Set 'on', and there are coloured striped 'grayscale' prints on both 32-bit WinXP and 64-bit Win7. Set 'off', and there's pure grayscale.

Strange a little bit, I was thinking auto-duplex constrains PGBK starting from next gen printers (x20/x21 ink type) up to now (x25/x26 and x50/x55/x51).

Good to know anyway

Ł.

 

[Łukasz]

According to this manual, the only time iP4200 is printing unidirectionally is when printing grayscale on envelopes.

I know that

Spoiler

Service Manual is claiming, that borderless printing (especially on plain paper) is bi-di mode, but in SM dedicated to next gen printers (eg. iP3600) it is stated, that borderless printing on plain paper is uni-directional.

It is about Canon Pixma SMs in general - they can't be trusted in all aspects. I have learned that hard way - especially pinouts of printhead connectors

However, it specifies that there indeed is a matter of the number of passes: 1 pass in normal colour and grayscale printing and 2 passes and more in borderless, photo paper, etc. Therefore it is clear that my banding issue occurs only when printing is done in 1 pass only. I cannot claim that I understand the exact mechanics of this, but perhaps you guys would find this info useful (and make a more informed prediction of my printer's prospects).

I'm not very sure, if these type of PH dysfunction can be covered just by multipass printing. I'll try to find someone to check that, cause none of my PHs is damaged in that way.
Note - most photo modes uses multipass and this type of PH error isn't spot first time. One should notice using multipass mode to be acceptable solution to cover 1/4 missing nozzles. But - who knows

Ł.

 

[elenhil]

An small update, if you will. Now my test prints look like this:

Note the lower half of the letters. It used to be solid black not so long ago.

Also, my full-size prints how have this wide-ish discoloured streak running near the bottom of the page:


Could this be related to the previously identified (?) cyan nozzle issue, or is this the a sign of the logic board damage you've warned me of?