I need to know how can I check the ink level. I press the scan copy, or fax buttons and appears a narrow line in black. How can I know if I still have enough ink for some impressions..

While on remove power cable from printer wait 2 min, attach power cable again, , or scan glass is dirty

Open the scanner lid and clean the narrow glass in the left-hand part of the scanning area. Look for remains from ink or corrector at the far end and wipe them out. The narrow glass should be entirely clear to make good copies from the feeder.

Check ink level, clean contacts on cartridge and machine.

This error occurs when printer fails detecting ink level or printer assume that no ink in the cartridge. We cannot use print, copy,scan, and fax function before the problem fixed. It's recommended for you to replace ink cartridge. To continue using the printer without replacing the cartridge we must deactivate ink level detection function. Be aware that printing in this condition can damage the printer while sending fax or scan is not problem.


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This error occurs when printer fails detecting ink level or printer assume that no ink in the cartridge. We cannot use print, copy,scan, and fax function before the problem fixed. It's recommended for you to replace ink cartridge. To continue using the printer without replacing the cartridge we must deactivate ink level detection function. Be aware that printing in this condition can damage the printer while sending fax or scan is not problem.

This error occurs when printer fails detecting ink level or printer assume that no ink in the cartridge. We cannot use print, copy,scan, and fax function before the problem fixed. It's recommended for you to replace ink cartridge. To continue using the printer without replacing the cartridge we must deactivate ink level detection function. Be aware that printing in this condition can damage the printer while sending fax or scan is not problem.

Original source: http://ij-forum.blogspot.com/2008/12/error-message-check-ink-u162u163.html#ixzz2Cpr4Be1K
This error occurs when printer fails detecting ink level or printer assume that no ink in the cartridge. We cannot use print, copy,scan, and fax function before the problem fixed. It's recommended for you to replace ink cartridge. To continue using the printer without replacing the cartridge we must deactivate ink level detection function. Be aware that printing in this condition can damage the printer while sending fax or scan is not problem.

Original source: http://ij-forum.blogspot.com/2008/12/error-message-check-ink-u162u163.html#ixzz2Cpr4Be1K

This section describes dialing and sending faxes directly using the Numeric buttons.

note:

• A PBX (Private Branch Exchange) is an on-site telephone switchboard. If your machine is connected through a PBX or other telephone switching systems, you have to dial the outside line access number first, and then the number of the party you are calling.
  

Sending a Fax with the Numeric Buttons .

Click here for other useful sending methods.


1. Preparing for sending a fax.(1) Make sure that the power is turned on.

(2) Load a document on the Platen Glass or in the ADF.

important:

• When sending a double-sided document, set the document on the Platen Glass. You cannot scan double-sided documents from the ADF.

(3) Press the FAX button.
The fax standby screen will appear.

(4) Adjust the density (scan contrast) or image quality (fax resolution) as necessary.
See "Adjusting the Sending Quality"

2. Sending the fax.

• When the document was loaded on the Platen Glass:

(1) Use the Numeric buttons to dial the recipient's number.

(2) Press the Color button for color sending, or the Black button for black & white sending.
important:

• Color sending requires that the recipient's fax machine supports color faxing.

(3) Press the OK button.
The machine starts sending the fax.
note: When loading two or more documents

• Load the next page, and press the same button as you pressed in (2) of step 2. Repeat the same procedure to scan all pages of the document, and press the OK button.
  
• When you have sent the first page with the Black button, the following pages will be sent in black and white.

When the document was loaded in the ADF:

(1) Use the Numeric buttons to dial the recipient's number.
(2) Press the Color button for color sending, or the Black button for black & white sending.
The machine scans the document automatically and starts sending the fax.
important:

• Color sending requires that the recipient's fax machine supports color faxing.

note:

• To cancel sending a fax, press the Stop button, and follow the instructions on the LCD.
  
  
• If documents remain in the ADF after pressing the Stop button during scanning, "Close the feeder cover [OK]Eject the document" will appear on the LCD. Press the OK button so that the remaining document is automatically fed out.

Automatic redialing

• When sending a fax and the recipient's line is busy, the machine will redial the number after a specified interval. Auto redial is enabled by default. Auto redial can be enabled or disabled by selecting ON or OFF. Select ON to specify the number of redialing in Redial times and redialing interval in Redial interval.

Redialing the Number Dialed with the Numeric Buttons

1.Prepare for sending a fax.
(1) Make sure that the power is turned on.
(2) Load a document on the Platen Glass or in the ADF.
(3) Press the FAX button.
The fax standby screen will appear.
(4) Adjust the image density (scan contrast) or quality (fax resolution) as necessary.
See "Adjusting the Sending Quality"
2. Select the telephone number recently dialed.
(1) Press the Redial/Pause button.
Most recently dialed fax number using the Numeric buttons will appear.
(2) Use the (-) or (+) button to select the number to redial.

(3) Press the OK button.
The selected number will appear in the fax standby screen.
3. Send the fax.
Press the Color button for color sending, or the Black button for black & white sending.
important:

• Color sending requires that the recipient's fax machine supports color faxing.

To check the ink levels from the HP Photosmart Software
1. In the HP Solution Center, click Settings, point to Print Settings, and then click Printer Toolbox.
NOTE: You can also open the Printer Toolbox from the Print Properties dialog box. In the Print Properties dialog box, click the Features tab, and then click the Printer Services button.
The Printer Toolbox appears.
2. Click the Estimated Ink Level tab.
The estimated ink levels for the print cartridges appear.

Or

Print a self-test report
1. Load A4 unused plain white paper into the input tray.
2. Press and hold the Cancel button and then press the Start Copy Color button.
The product prints a self-test report, which might indicate the source of the printing problem.
3. Make sure the test patterns show a complete grid and the thick color lines are complete.
• If more than a few lines in a pattern are broken, this might indicate a problem with the nozzles. You might need to clean the print cartridges.
• If the black line is missing, faded, streaked, or shows lines, this might indicate a problem with the black or photo print cartridge in the right slot.
• If any of the color lines are missing, faded, streaked, or show lines, this might indicate a problem with the tri-color print cartridge in the left slot.

the glass need to be clean. Even though the glass look clean lines in the copies or faxes can appear. And its normally when using the document feeder. Lift the lit and clean both glasses. The big one and the narrow one at the very left. Use windex or something like that to clean it and try again. If the lines also appear when printing from the pc the issue can be other (fuser, toner, or rollers) try running a couple of cleaning pages from the service menu: press the wrench and with the arrows look for service, press ok and look for cleaning page and press ok again. Good luck

Open the auto sheet feeder (where you place your originals), look underneath and you will see a narrow "scanner" glass that the originals are scanned across. Clean this thoroughly with glass cleaner (or water) - there is probably correction fluid or some other foreign dirt on it. If you make a copy for yourself (before and after) it gives a good indication of the quality you are sending to fax recipients.

good luck, and please rate solution

I beleive you are not able to make a color copy, once try to scan from the computer or all-in-one to check whether the scanner mechanism is working properly or not, if the scan comes out fine then remove the color cartridge and clean the copper contacts of the cartridge with soft cotton cloth and also check the ink level of the cartridge, if the issue persists replace the color cartridge and if even the scan does not comes out good then there is an issue with the scanner mechanism.

As some fax machines are not capable of receiving color faxes, legal size faxes, or faxes at 200x200 dpi resolution, make sure you are sending an A4 or letter size (not legal size) page at standard resolution:
Press the Black button for a black-and-white fax. Press the Quality button to check the selected resolution.
Make sure the All-In-One has enough memory free when you want to save the scanned documents into memory before sending the fax. Please refer to the following document: Click here to link to the relevant document.
Note: The scanned documents will only be saved in the memory before the whole fax is sent if the Scan Before Dial option is turned on. (This is the factory default.) Up to 50 black-and-white fax pages can be stored in memory at standard resolution when there are no pending faxes in the queue.
Turn off the Scan Before Dial option by pressing the following keys on the operator panel:
Press the Fax button, then press Options 15 times to get to ADVANCED FAX mode.
Press Select.
Press Options nine times until SCAN BEFORE DIAL appears on the LCD display.
Change the setting from Yes to No using the + (right arrow) button.
Press Select.
Note: The Scan Before Dial option controls whether a document is scanned before a call is dialed. This parameter only applies to a mono fax that uses either 200x100 or 200x200 resolution. Higher resolution mono faxes and all color faxes are scanned after the call is dialed and the receiving machine's capabilities are known.
Lower the fax transmission speed to 14400 or even 9600 bps, as some older fax machines are not capable of receiving a fax at a high speed. To do so:
Press the Fax button, then press Options 15 times to get to ADVANCED FAX.
Press Select.
Press Options 10 times until MAX SEND SPEED appears on the LCD display.
Change it to 9600 BPS using the - (left arrow) button.
Press Select.
Turn off ECM (Error Correction Mode) by pressing the following keys on the operator panel:
Press the Fax button, then press Options 15 times to get to ADVANCED FAX.
Press Select.
Press Options 11 times until ERROR CORRECTION appears on the LCD display.
Change the setting from On to Off using the + (right arrow) button.
Press Select.
Note: Turning off this option makes it possible to receive a fax when the receiver fax machine does not support certain error correction modes. The X6100 Series only supports 1-D MH encoding with the error correction. Fax transmissions without ECM and other ECM types can result in bad quality on the received page.