When printing faint white horizontal lines are across each picture

The machine needs to be cleaned.

T'Con board fault.
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Hi
If a single inkjet in your printer is not functioning then output will appear as a horizontal line across the page. If one of the jets is on all of the time then output will have black or colored lines across the page. Use the following steps to isolate the problem: - Replace the ink cartridge - Check the flexible cabling for continuity and for short circuits between adjacent conductors - Exchange the control board for a good one - Finally check the power supply
Good Luck

The drum roller is damaged. You must be careful and spin the cylinder. do not touch the roller. You probably have a line in the roller that causes this issue. Each time i have seen this problem, this was the cause.

if this line is in the picture, that is possible burn in screen. if you have a black bar at the top or faint white lines that come down from top this is caused by defective filters in vertical circuit or bad vertical output. mch

bad vertical chip ic

Your post "...it prints very faint horizontal lines in color..." is indicative that indeed your color printheads are clogged and would need repetitive deep head cleaning. This is of course would require that you keep on cleaning until such time as the faint color lines have turned to legible print.

Sounds like the flyback transformer is bad. couple of 100 dollars if it is that

This is usually caused by a problem in the Horizontal Output section, around the Horizontal Output transformer usually a capacitor or diode going or gone faulty... the line you see are the Horizontal "Retrace" lines that are useually "Hidden" when the circuit is OK..