IBM 5150 Hardware Maintenance Manual page 159

Error
Description
Diagnostic Action
Printing
1.
Check for adequate ink on ribbon or
Too damaged ribbon. Replace cartridge if
Light
needed.
Poor 2. Check ribbon cartridge for binding by
Print manually advancing ribbon. Replace if
Quality
binding.
3. Visually check for worn or broken ribbon
drive gears. Replace Carriage Drive assembly
if damaged. (See Section 3, "Removal/
Replacement. ")
4. Check for bent ribbon shield. Replace if
necessary. (See Section 3, "Removal/
Replacement. ")
5. Check print head for broken or binding
wires. Replace print head if wires are
broken or bound. (See Section 3,
"Removal/Replacemen
t.")
6. Verify that print head gap is 0.6 to
0.65 mm (0.024 to 0.026 in.) with the lever
in the center position. (See Section 3,
"Removal/Replacement.")
7. Check print head for loose mounting.
Reseat. (See Section 3, "Removal/
Replacement. ")
8. Check for loose or damaged platen, print
head carriage shafts, or print mechanism
frame. Replace Print Mechanism if needed.
(See Section 3, "Removal/Replacement.")
1400-18