Resolution:
CAUSE 1: Damaged ribbon shield

SOLUTION 1: Inspect the shield, and repair or replace.

- 4800 and 4900 series: Following the instructions in the user's manual for changing the print modules, remove the ribbon deck, but do not remove the modules.

- The ribbon shield is the thin metal shield that goes between the ribbon and the paper.

CAUTION- the ribbon shield is very thin and sharp- it will cut very easily.

- Inspect the ribbon shield. The shield should have a number of holes for the print wires to pass through. Any damage will cause ribbon problems. Inspect the edges of the shield for burrs or damage. If the shield is damaged, it should be replaced.

CAUSE 2: Damaged print wires.

SOLUTION 2: Remove and inspect the print modules. If any print wires are over-extended or bent, replace the module.

CAUSE 3: Faulty ribbon weld sense circuit.

The ribbon consists of fabric ultrasonically welded together at the ends to make a continuous loop. Printing over the weld causes print quality issues, since the weld does not pick up ink. To avoid this, an oblong hole is located just before the weld. The ribbon weld sensor is an optical sensor that detects the weld. When the weld is detected, the printer suspends printing long enough for the weld to skip across the print line. When the printer goes into suspend mode, the display shows ONLINE: SUSPEND. The ribbon weld timer is also reset when the printer detects the ribbon weld.

If a fault occurs in the ribbon weld sensor, the typical symptom is a display of FAULT: RIBBON WELD. The weld sensor can be disabled by setting printer control strap B38 to IN.

If the sensor is disabled, and there is a a fault in the ribbon weld sensor circuit, the printer will print over the weld sensor hole, and can cause the ribbon to tear and jam.

SOLUTION 3: IF the sensor is disabled, enable it. If the rJ or FAULT: RIBBON WELD displays are shown, troubleshoot and repair the ribbon weld circuit.