# Canon MP640 not printing in black



## royster2 (Nov 27, 2011)

My Canon MP640 has suddenly decided not to print anything using the black cartridges. I've replaced both black cartridges but it still won't print. Can use any colour albeit quite faded because of lack of black input. Help please????


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## pip22 (Aug 22, 2004)

The black ink-feed nozzles (inside the printer, not on the cartridge) may be blocked with dried-up ink so try running the nozzle cleaning tool several times.

If that doesn't clear it, the blockage may be quite bad, requiring a different cleaning method:

1) Remove black cartridge and put a few drops of alcohol-based (eg isopropyl alcohol) solvent into the small hole at the bottom of the cartridge cradle. Leave several hours or overnight before trying to print again.

2) Remove black cartridge and replace it with a cleaning cartridge which contains solvent. You can buy them online, for example here: Cleaning Cartridges,Cleaning Flush

And here: Cleaning Cartridges For Epson, Canon, Brother And HP Inkjet Printers


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