IBM 6400 series Maintenance Manual page 91

If the message appears, replace the power supply board.
5. Power on the printer.
If the message appears, replace the shuttle frame assembly.
087 PLATEN OPEN TIMEOUT
CLOSE PLATEN
1. On a coax interface, the forms thickness lever has been open for at least one
minute. Load paper.
Close the forms thickness lever. Press Stop.
2. Run a print test. If a platen open or close platen message appears, power off the
printer. Remove the paper guide assembly or pedestal top cover. Disconnect
connector P107 from the CMX controller board. Check continuity of the platen
interlock switch cable from P107 to the switch.
Replace the platen interlock switch assembly if it fails continuity test.
(Refer to Appendix A, Switch Assembly, Platen Interlock.)
3. Check that the platen interlock switch is not loose.
Tighten the screws securing the platen interlock switch
4. Check the condition and tension of the platen open belt.
Adjust the platen open belt. Replace the belt if it is damaged.
5. Check the platen open pulley and the platen pulley for looseness.
Bottom out the platen open motor pulley on the motor shaft and torque
the 1/16 inch set screw to 9
the 7/64 inch setscrew in the platen shaft pulley, then open and close the
forms thickness lever and check that the platen pulley setscrew does not
hit the left ribbon guide.
6. Disconnect connector P106 from the CMX controller board. Check the resistance
of connector P106/PLAT M. (Refer to the Main Wire Harness Test Tables on page
297.)
Replace the platen open motor if it fails the resistance test.
7. Run a print test.
If a platen open or close platen message appears, replace the CMX
controller board. Record the message and return it with the defective
board.
Troubleshooting
2 inch-pounds (1.02 0.23 N m). Tighten
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