Samsung SLM4370LX

• Code: U1-234J, U1-234P
• Description: Fuser Unit Failure: #U1-234J. Turn off then on.
  Fuser Unit Failure: #U1-234P. Turn off then on.
• Causes: The temperature control of fuser unit is abnormal. The fuser temperature has risen above the normal value.
• Remedy: 1) Turn the machine off then on.
  2) Turn the machine off. Re-install the fuser unit. Then turn the machine on.
  3) If the problem persists, remove the fuser unit.
  4) Check the fuser components. • Check if the thermistor is assembled correctly. • Check if the thermostat is connected. • Check if the center and side lamps are in short status. (Measure the resistance value between the common-center and common-side.)
  5) If there are any defective parts in step5, replace the fuser unit.
  6) If the problem persists, replace these parts in regular sequence. • Fuser Drive Board • Main board • SMPS board

• Code: U2-1112
• Description: LSU Failure: #U2-1112. Please turn off then on.
• Causes: LSU motor does not operate or it operates abnormally. Motor ready signal is abnormal.
• Remedy: 1) Turn the machine off then on. Check for the LSU motor operation sound during warm-up.
  2) Print a demo page to check that the machine operates normally.
  3) If the problem persists, check the following : • If the LSU motor makes a sound, a) Enter SVC mode to check the LSU motor ready signal. b) Select “LSU Motor1 Run Ready”. ( Diagnostics > Engine Diagnostics > Engine Test Routines > 110-0000) c) Press ‘Start’ button. Check that the status has changed to ‘Executing -> Low -> High’. d) If the status has not changed, the motor ready signal is abnormal. Replace the LSU. • If the LSU motor does not makes a sound, a) Turn the machine off. Unplug and reconnect the LSU cable. Check that the LSU motor make a sound after turning the machine on. b) If the LSU Cable is defective, replace it. Check that the LSU motor make a sound after turning the machine on. c) If the problem persists, replace the LSU.

• Code: U2-1113
• Description: LSU Failure: #U2-1113. Please turn off then on.
• Causes: LSU Hsync signal can not be detected correctly. LSU Hsync signal is abnormal.
• Remedy: 1) Turn the machine off then on.
  2) Print a demo page to check that the machine operates normally.
  3) If the problem persists, check the following : a) Enter SVC mode to check the LSU Hsync signal. b) Select “LSU Hsync4”. ( Diagnostics > Engine Diagnostics > Engine Test Routines > 110-0170) c) Press ‘Start’ button. Check that the status has changed to ‘Executing -> Low -> High’. d) If the status has not changed, LSU Hsync signal is abnormal. e) Turn the machine off. Unplug and reconnect the LSU cable. Check LSU Hsync signal once again. f) If the problem persists, replace the LSU.

• Code: U3-3211, U3-3213, U3-3214
• Description: Original paper jam inside the scanner
• Causes: Original jam has occurred around the scan in roller and regi roller.
• Remedy: 1) Check if the pick up motor operates normally. a) Check if the paper jam has occurred on DSDF tray.
  2) Open the DSDF cover. Remove the paper on Guide-Pick up Assy.
  3) Check if the actuator and pick up assy operate normally. a) Check the operation of the regi sensor. b) If the regi sensor operation is OK, check the followings.
  i) Remove 1 screw and push the hook. ii) Release the Stacker by pulling it to the direction of arrow. iii) Release the rear cover. iv) Remove the Bracket Hinge. v) Remove the Cover-Open Assy. Remove 6 screws. And remove the bottom cover. vi) Check if the sensor and actuator are assembled correctly. c) When lifting the pick up assy, check that 2 rollers contacts normally.
  4) Check if there are any obstacles or contamination on the paper path. Remove it.
  5) Close the DSDF cover.
  6) Open the DSDF unit. Check if the reflection film is contaminated. Clean it.
  7) Close the DSDF unit.

• Code: U3-3311, U3-3313, U3-3314
• Description: Original paper jam inside the scanner
• Causes: Original jam has occurred around the scan in roller and regi roller.
• Remedy: 1) Check if the pick up motor operates normally. a) Check if the paper jam has occurred on DSDF tray.
  2) Open the DSDF cover. Remove the paper on Guide-Pick up Assy.
  3) Check if the actuator and pick up assy operate normally. a) Check the operation of the regi sensor actuator and feed out sensor actuator. b) If the regi sensor operation is OK, check the followings. i) Remove 1 screw and push the hook. ii) Release the Stacker by pulling it to the direction of arrow. iii) Release the rear cover. iv) Remove the Bracket Hinge. v) Remove the Cover-Open Assy. Remove 6 screws. And remove the bottom cover. vi) Check if the sensor and actuator are assembled correctly.
  4) Check if there are any obstacles or contamination on the paper path. Remove it.
  5) Close the DSDF cover.
  6) Open the DSDF unit. a) Check if the reflection film is contaminated. Clean it. b) If the problem persists, check the followings. i) Open the DSDF cover. ii) Pull the lever and release the pick up Assy. iii) Push and release the Stacker Assy. iv) Remove the Guide Pick Up Upper after removing 4 screws. v) Check if the sensor is assembled correctly. If the sensor is defective, replace it.
  7) Check if the simplex scan sensor connector is connected correctly.
  8) Close the DSDF unit.

• Code: U3-3411, U3-3413, U3-3414
• Description: Original paper jam inside the scanner
• Causes: Original jam has occurred around the scan in roller and regi roller.
• Remedy: 1) Check if the pick up motor operates normally.
  2) Open the DSDF cover. Check if the paper jam is occurred.
  3) Pull the green lever of the Guide Exit Lower. Remove the jammed paper.
  4) Check if there are any obstacles or contamination on the paper path. Remove it.
  5) If the problem persists, check the followings. a) Remove the DSDF Unit and white sponge. b) Open the Guide Exit Lower Assy. c) Check the sensor. d) Remove the screw. Check the sensor connection, If the connection is OK, replace the sensor. 6) Push the white bar. Check if it returns in original condition. 7) Close the DSDF unit.