The Canon Pixma IP 4000 printer has a self-diagnosing print head error notification system. Generally the "Alarm/Power" light will flash and tell you what kind of problem you might be having with your print head. You can also run tests yourself to identify problems.
Look at the "Alarm/Power" light and see how many times it's flashing. If it flashes orange 11 times consecutively, that means there is a print head alignment issue. Perform deep cleaning, then move the printer away from any strong light sources. To deep clean, click the Maintenance tab in the "Printers" folder. Then click the "Deep Cleaning" icon. You can select all colours, black, or selected colours. Click on "Execute."
If it flashes orange five times consecutively, that means there is a print head error. Reseat the print head, then reset the printer. To reseat the print head, make sure the printer is on. Open the paper output tray and top cover. Make sure the print head holder is in the centre and open the inner cover. remove all the ink tanks. Raise the print head lock lever and remove the print head. Reseat the print head and lock the lever. Replace the ink tanks.
Check to see if the ink is ejecting normally from the print head nozzles by running a test. Press and hold the "Resume/cancel" button. When the Power lamp flashes twice, release the button. Examine the printed output. Use the references below to compare your output to what Canon suggest is correct. If the output is incorrect, then perform deep cleaning, if necessary repeat twice.
Replace the ink tanks if you're unable to get a good result by following the previous steps. make sure the printer is on, lift the top cover. The print head holder will move to the centre. Press on the tab to release the tank. Unwrap a new tank. Make sure you can see the air hole and insert the new tank until you hear a firm click. Repeat for the other tanks if you suspect from your print test that they have failed.
Make sure the tanks are snapped in properly too.
Avoid performing more than three deep cleanings in a twenty-four hour period.