IBM 6400 Maintenance Information Manual page 129

Symptom
Shuttle does not move
Table 5. General Symptom List
Shuttle
1. Power down the printer. Remove the shuttle cover. Adjust the
gap between the MPU assembly and the flywheel to 0.010 ±
.001 inch (0.254 ± 0.025 mm). Torque the 7/16 inch MPU clamp
screw to 18 ± 1 inch-pounds (2.03 ± 0.11 N•m).
2. Check that the MPU cable is connected to J03 on the
mechanism base. Check that the shuttle motor cable is
connected to J02 on the mechanism base.
3. Remove the paper guide assembly or pedestal top cover. Check
that the shuttle motor drive cable is connected to J116 on the
CMX controller board.
4. Check and adjust the platen gap.
5. Inspect the ribbon mask for bends or deformation that snag and
interfere with shuttle movement. Make sure the hammer bank
cover assembly is correctly installed on its mounting pegs.
Reinstall the hammer bank cover assembly. Replace a
damaged or deformed hammer bank cover assembly.
6. Check continuity of the shuttle motor drive cable assembly.
Replace shuttle motor drive cable assembly if it fails continuity
test.
7. Power up the printer. Run a Shuttle Slow or Shuttle Fast test. If
the shuttle does not move, replace the shuttle frame assembly.
8. Power up the printer. Run a Shuttle Slow or Shuttle Fast test. If
the shuttle does not move, replace the power supply board.
9. Power up the printer. Run a Shuttle Slow or Shuttle Fast test. If
the shuttle does not move, replace the CMX controller board.
General Symptom List
Corrective Action
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