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Action
Yes
No
Step 6
Check the LSU for damages, and replace if necessary.
Installation note:
Mechanical and electronic LSU adjustments
are required to complete the installation of the LSU. See
“Printhead assembly adjustments” on page 204
Does the problem remain?
Go to step 7.
The problem is
solved.
Step 7
Check the LSU and controller board connector for damaged or
bent pins. Replace the part with damaged pins.
Does the problem remain?
Go to step 8.
The problem is
solved.
Step 8
Replace the controller board.
Does the problem remain?
Contact the next
level of support.
The problem is
solved.
121 errors
121 error messages
Error code Description
Action
121.07
Fuser has been on for more than allowed after a
gap blowout, and the temperature is still too cold.
Go to
“Fuser service check” on page 127
.
121.08
Fuser was under temp when page was in fuser.
121.20
Fuser undertemp during steady state control. Can
occur in printing or standby modes.
121.22
Fuser did not warm enough to start line voltage
detection.
121.23
Fuser took too long to heat to line detection temp.
121.24
Fuser never reached detection temperature.
121.25
After line voltage detection, control did not roll
over to steady state control in time.
121.26
Failed to reach temperature during warm up.
121.28
Failed to reach EP warm up temperature in time.
121.29
Fuser failed to reach pre
‑
heat temperature for
motor start during warm up.
4514-330
Diagnostics and troubleshooting
126
Summary of Contents for MS312
Page 11: ...Part number index 335 Part name index 339 4514 330 Table of contents 11 ...
Page 12: ...4514 330 Table of contents 12 ...
Page 182: ...4514 330 182 ...
Page 214: ...5 Remove the three screws B and then remove the left front mount B 4514 330 Parts removal 214 ...
Page 230: ...5 Remove the four screws B and then remove the right front mount B 4514 330 Parts removal 230 ...
Page 234: ...b Set the spring over the plunger 4514 330 Parts removal 234 ...
Page 240: ...3 Squeeze the latches B to release the left and right links B 4514 330 Parts removal 240 ...
Page 267: ...11 Disconnect the two springs D D 4514 330 Parts removal 267 ...
Page 284: ...3 Swing the right cover backward to remove 4 Remove the screw D 4514 330 Parts removal 284 ...
Page 286: ...4514 330 286 ...
Page 291: ...4514 330 291 ...
Page 293: ...Assembly 1 Covers 4514 330 Parts catalog 293 ...
Page 295: ...Assembly 2 Electronics 1 1 2 3 4 5 7 8 9 6 4514 330 Parts catalog 295 ...
Page 297: ...Assembly 3 Electronics 2 4 3 2 1 6 5 4514 330 Parts catalog 297 ...
Page 299: ...4514 330 Parts catalog 299 ...
Page 300: ...Assembly 4 Frame 2 5 6 9 10 11 13 14 12 8 1 4 4 3 7 4514 330 Parts catalog 300 ...
Page 302: ...4514 330 Parts catalog 302 ...
Page 303: ...Assembly 5 Option trays 3 4 5 6 1 2 4514 330 Parts catalog 303 ...
Page 306: ...4514 330 Parts catalog 306 ...
Page 308: ...4514 330 308 ...
Page 312: ...4514 330 312 ...
Page 314: ...4514 330 314 ...
Page 326: ...4514 330 326 ...
Page 338: ...4514 330 Part number index 338 ...
Page 342: ...4514 330 Part name index 342 ...