PRINT IS TOO LIGHT

My first thought is that the numbers being "hammered" against the paper are not reaching far enough. Test this theory by putting two layers of paper into the paper feed, (Fold the end of the roll over onto itself) and try printing again. It could be designed for a thicker paper.
Alternatively the new ribbon may also have dried out. Rub the ink ribbon with a paper, or pencil eraser and see if the ink readily comes off, perhaps use a pencil eraser to press it against the paper being fed through the machine.

These are diagnostics to find the error. Further investigation might be to see if there is any particles in the machine preventing it from hammering the numbers against the paper. Something might be in the way of the moving parts, something about the size of a paper hole punch paper, or pencil shaving. Shaking it vigorously upside down might solve this problem.

Good luck ;)

Can you attach a sample? Config would be fine.

they usually have a metal plate in the bottom that you remove and there is a switch panel where you can adjust the deep ( how dark it will look )

The red light means out of paper or ink ribbon. Some people chose not to use the ink ribbon and get thermal direct paper which requires no ink ribbon but The red light means out of paper or ink ribbon. Some people chose not to use the ink ribbon and get thermal direct paper which requires no ink ribbon but the printer has to be told by the driver not to expect ribbon or the red light will come on. Also not having the correct paper height set in the driver will make the red light come on as well so check the advanced tab in the properties of the driver then click printing defaults. In the ZDesigner driver height and width are entered there. In the zebra universal, its the same path but one extra click. Click paper output and enter the size.

First try a new IBM brand ribbon part # ends in 999. NCR paper can be difficult try the code "Q" this should increase thr impression.

DickyO

You have to make a platen adjustment (on the left side move it back).

Put in a multi part form, if the carbons print well then try a fresh ribbon,. not one that has been sitting around for a long time. If it is bad check for debris around the print hammer, If its clean either the print solenoid is gummy or the solenoid cap is broken.

DickyO

MAKE SURE RIBBON IS INSTALLED CORRECTLY, SHOULD BE BETWEEN "FINGERS" NEXT TO CARDHOLDER AND CARDHOLDER.
COULD BE A BAD BATCH OF RIBBONS
SOMETIMES CORRECTABLE RIBBON DOESN'T PRINT WELL ON CERTAIN TYPES OF PAPER, SUCH AS "NCR" PAPER, TEXTURED, SLICK OR ANY PAPER THAT HAS BEEN THROUGH A PRINTING PROCESS (FORMS, LETTERHEADS, ETC.)
CHECK RIBBON ITSELF. THE CARBON SHOULD BE A FAIRLY EVEN LAYER. IF THERE ARE BLANK PLACES----

if you are using software that using printer please the s600 printer driver to direct thermal mode to solve the problem.

Remove and reinstall the ribbon. Also, while the ribbon is out, try spinning the knob on it.