hardware failure - No black ink printing for MFC 490CW Brother printer?

I have a Brother model MFC 490CW color printer than has three color ink and one black ink cartridge.

I've replaced the black ink cartridge, but I still get no black ink being printed, the three color inks are printing correctly. What could be going wrong and how might I fix this? The printer had been idle for about nine months, could there be some kind of clogging? The printer's clean utility did not help.

Answer

I cleared the ink jets on a brother MFC-490CW on the first try.

1. I had no black after 3 or 4 Power_P ALL cycles.


2. I took the alcohol injection route.


3. I removed all 4 ink cartridges.


4. Using a flashlight,I found the inlet tube for the black ink.


5. Using the thin rubber tube from an antifreeze tester which fit snugly over the black ink inlet tube,I injected about 1/4-1/2 oz. of Everclear(90% ethyl alcohol) into the tube under pressure.


6. replaced ink cartridges.


7. I ran the Power_P cycle once more.


8. Black functioned 99% on first test page and 100% on second.