I replaced the clear ink tank on mx7600 and the message "the clear ink is empty" will not go away nor will it print in black. The brand new Canon brand clear ink can be seen on the ink tank itself and in small the pool around the clear ink tank prongs so it appears to be getting ink. The printer will print on 'high glossy photo paper' settings, but will not print black on plain paper. It seems the printer is not detecting that there is clear ink available. Could something be plugged that's keeping the clear ink from getting to the print head or is it something else.

INK PROBLEM
Inkjet printers need to be used frequently to prevent ink drying out and blocking the print head nozzles.
If the print head cleaning maintenance routine does not clear the blockages, then print head needs replacing, but it may be expensive.
It may be more cost effective to buy a later model and better printer than replace the print head.

This section explains the way to confirm the ink status and the procedure to replace ink tanks. When ink runs out or other errors occur, an error message is displayed on the LCD to inform you of the error. See "An Error Message Is Displayed on the LCD".
When printing from your computer, error messages appear on your computer screen as well.

NOTE

Be sure to install the ink tanks in the correct order indicated by the label on the Print Head Holder.
The machine will not print if an ink tank is installed in the incorrect position.

• With the LCD of this Machine
• With the Ink Lamps
• Getting the Clear Ink Status Information

With the LCD of this MachineMake sure that the machine is turned on, then press the COPY, FAX, SCAN, or MEMORY CARD button. The current ink level will be displayed on the LCD for a few seconds.

(A) Confirm whether any symbols are displayed here.

Color or black ink is low. You can continue printing for a while, but we recommend you to have a new ink tank available.Color or black ink may have run out. See"An Error Message Is Displayed on the LCD".
REFERENCE

The ink status information is also displayed on the screen that appears during printing.
An error message may be displayed on the LCD during printing.

Machine detected ink out condition. See "An Error Message Is Displayed on the LCD" and take appropriate action.
(B) Empty ink tank.With the Ink LampsYou can confirm the status of each ink tank by the ink lamps. Open the Scanning Unit (Printer Cover) of the machine to confirm how the ink lamps light or flash.

• Ink lamp is on

The ink tank is correctly set and there is enough ink remaining to print.

• Ink lamp is flashing

Flashing slowly (at around 3-second intervals)


Ink is low. You can continue printing for a while, but we recommend you to have a new ink tank available.
Flashing quickly (at around 1-second intervals)


The ink tank is inserted in the wrong position or it is empty. Ensure that the ink tank is in the correct position as directed by the label on the Print Head Holder. If the position is correct and its lamp flashes, it is empty. Replace it with a new one.

• Ink lamp is off

The ink tank is not set properly or the function for detecting the remaining ink level is disabled.

If the ink tank is not set properly, press the mark on the ink tank until the tank clicks into place. If it does not click into place, make sure that the orange protective cap has been removed from the bottom of the ink tank.
If the function for detecting the remaining ink level is disabled, replace the ink tank with anew one. See "Replacing Ink Tanks".
If the lamps are still off after reinserting the ink tanks, there has been an error and the
machine cannot print. Check the error message displayed on the LCD. See "An Error
Message Is Displayed on the LCD".
Getting the Clear Ink Status InformationClear ink is used only when printing on plain paper.
When Plain paper (Cassette) is selected for Media type and printing begins when clear ink (PGI-9Clear) is low, a message will be displayed in the LCD.

(A) Confirm whether a symbol is displayed here.

The clear ink is low. You can continue printing for a while, but we recommend you to have a new ink tank available.The clear ink tank is empty. See ""The clear ink tank is empty. Replacing the ink tank is recommended." U045" and take appropriate action.
NOTE

• The ink status information is also displayed on the screen that appears during printing.
• Clear ink is used only when printing on plain paper. Therefore, it is possible to print on photo paper, or any type of paper other than plain paper, loaded in the Rear Tray, even if clear ink has run out.

The following error message will be displayed on the LCD when the clear ink has run out during printing on plain paper.

Refer to "Replacing Ink Tanks"If you continue printing under the clear ink out condition, see ""The clear Ink has run out. Replace the ink tank." U165/U166" and take appropriate action.When the clear ink hasrun out, printing on plain paper from the Cassette is not possible. The fax, which is received under the clear ink out condition, will be stored in memory.
NOTE

It is possible to print on photo paper, or any media type other than plain paper, loaded in the Rear Tray, even if clear ink has run out.

I have workaround for the empty tank issue:
- buy or borrow another not empty tank
- place it in
- start the printer
- it recognises the "new" tank
- turn off the printer
- put back the old, empty, but refilled tank
- turn on the printer
- print something
- it will pop up a dialogue window saying
"The ink level of the black/color tank cannot be
determined. The ink level determining function will be
disabled for the black/color tank.
If you want to continue printing without this function
press the Start button on the printer."
- Press the Start button on the printer and ignore the
button 'Cancel Printing' appearing on the dialogue window.
- The dialog window disappears.

You can print your refilled tank as many times you want from this time.

When you go to 'Printers /Canon /Properties /Maintenance / Printer Status / Ink Information' it says that the ink level measuring function has been disabled for: black [40] / color[41]. You can ignore this this message, the printer will work perfectly without this stupid function.

Change the cartridge ...


but, in case E3

I have workaround for the empty tank issue:
- buy or borrow another not empty tank
- place it in
- start the printer
- it recognises the "new" tank
- turn off the printer
- put back the old, empty, but refilled tank
- turn on the printer
- print something
- it will pop up a dialogue window saying
"The ink level of the black/color tank cannot be
determined. The ink level determining function will be
disabled for the black/color tank.
If you want to continue printing without this function
press the Start button on the printer."
- Press the Start button on the printer and ignore the
button 'Cancel Printing' appearing on the dialogue window.
- The dialog window disappears.

You can print your refilled tank as many times you want from this time.

When you go to 'Printers /Canon /Properties /Maintenance / Printer Status / Ink Information' it says that the ink level measuring function has been disabled for: black [40] / color[41]. You can ignore this this message, the printer will work perfectly without this stupid function.

1. If replacing both ink tanks, remove and replace each one individually.
   
   
2. Make sure the device is powered on.
   
   
3. Lift the scan unit until it locks into place. When the machine is ON and the scan unit is lifted, the paper output tray automatically opens.
4. Open the inner cover.
5. Hold the tab and pull it forward to release the ink tank.
   
   
6. Lift out the ink tank.
   
   
7. Remove the new ink tank from its packaging.
   
   
8. Hold the ink tank and remove the protective cap.
9. Insert the ink tank into the empty slot on the print head.
10. If you need to replace the other ink tank, repeat steps 4 to 8.
    
    
11. Close the inner cover.
    
    
12. Return the scan unit to its original position. The LCD displays a message asking if you replaced an ink tank.
    
    
13. Press [<] to select <YES>.
    
    
    
14. The LCD displays a message asking if you replaced the black ink tank.
    
    
15. If you replaced the black ink tank, press [<]. If you did not, press [>].
    
    
16. The LCD displays a message asking if you replaced the color ink tank.
    
    
17. If you replaced the color ink tank, press [<]. If you did not, press [>].
    
    
18. The ink counter is now reset.
    
    
19. If additional ink tanks need to be replaced, replace them now.

I had the same problem. My mp630 is also only 4 months old. I replaced all colour ink cartrdiges(inc black), but was only able to release the function for detecting the ink levels for magenta and cyan. Yellow and black then started giving error message U043, with them alternating between working, but never working at the same time. Getting them all clicked in with the lights glowing red does not solve the problem, as once the printer cover is closed, the same error message turns up. The only thing that worked for me is moving the chip slightly out of alignment, by pushing the sliding chip holder, and I only had to do this twice before they all started working and the printer was unlocked.

I believe that he is reffering to the waste ink tank where the cartriges stop to the right when not being used. There are two small foam pads over there.
I cleaned mine by opening lid and have carriage run to the left, then I reach in with a q-tip and press down repeatly until q-tips are almost clean. You will need a flashlight to see waht you are doing.

I had the same problem -- error message saying two cyan print tanks installed. Nothing helped (including disconnecting power cord). Then found I had an older cyan print tank still in its pack on hand, Installed that. No further problems. Assume this means print tank giving error is part of a faulty batch so am returning to retailer for refund from Canon.

I had the u043 problem on the blue cartridge on my mp830.

I was using non-original replacement inks but re-using the chips from the originals - replacing the blue cartridge would cause it randomly work but i then noticed the chip holder was not centred so I realigned it and hey presto! the problem was solved first time.

:)

Hello, I found this in a repair manual for the MP830. summery is to press and hold the stop/reset button for 5 or more seconds. I copied the info from the manual too. The remaining ink amount unknown. [1683] (Applicable ink tank icon) The remaining level of the following ink cannot be correctly detected. An ink tank which has once been empty is installed. Replace the applicable ink tank with a new one. Printing with a once-empty or refilled ink tank can damage the print head. If printing is continued without replacing the refilled ink tank, press the Stop/Reset button for 5 sec. or longer to record the use of a refilled ink tank. Note: After the above operation, the function to detect the remaining ink amount is disabled.