6. Exploded Views and Parts List 7. Electrical Parts List 8. Block Diagram 9. Connection Diagram 10. Schematic Diagrams - This Service Manual is a property of Samsung Electronics Co.,Ltd. Any unauthorized use of Manual can be punished under applicable International and/or domestic law. -...
ABRE. EVITAR EXPONERSE AL RAYO. 12. Do not touch the surface of the photo-sensitive drum as marks or scratches may impair print qual- CAUTION : Avoid exposure to invisible laser radiation when the ity. development unit is not installed. Samsung Electronics...
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ESDs. 4. Use only a ground-tip soldering iron when soldering or desoldering ESDs. 5. Use only anti-static solder removal device. Some sol- der removal devices are not rated as “anti- static;”these can accumulate sufficient electrical Samsung Electronics...
During Sleep : Less than 30W Consumption Less than 30W during 1 hour when it turned on Certification & Compliance C-UL, TUV, FCC, CDRH, CE, CB Acoustic Noise Stand by : Less than 36dB, Operating : Less than 49dB Toner Supply Print Cartridge Samsung Electronics...
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- XON/XOFF, DTR/DST Protocol - Rubust XON for XON/XOFF LOCALTALK - Macintosh Host Interface 230.4KBPS, SDLC, FMO Coding, RS-232C Network Interface 100--Base -Tx or 10 Base T Autoselect Interface Switching Automatic (Serial & Parallel) Interface Time Out 5 min (max.) Samsung Electronics...
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INTA Interrupt Acknowledge collector supply voltage (dc) INTR Interrupt Request Video data from controller Pound(s) Video data output LDON laser Diode On vert vertical linearit Vp-p peak-to-peak voltage lock bus lock variable resistor Lready LSU power ready millimeter(s) Samsung Electronics...
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Serial Communications Controller Dots Per Inch (resolution) DRAM Dynamic Random Access Memory SMPS Switching Mode Power Supply Digital Voltmeter Small Outline Package EEPROM Electronically Erasable Transfer High Voltage Programmable Read Only Memory Tri-State Image Control Unit Video Control Unit Samsung Electronics...
10. A defective trimming resistor cannot be adjusted externally. Replace with an ordinary variable resistor. 11. Always inspect the work with a magnifying lens. Check after installing cold solder joints, etc. Samsung Electronics...
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2. Using a special desoldering iron: a. Use small flat-blade tips. b. Heat both ends of the part simultaneously. c. When the solder melts, grasp and remove the part with the soldering iron tips. d. Remove the old solder with desoldering wire. Samsung Electronics...
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(suggested : temperature : 7, air-blow:4) c. Engage the IC removing tool. d. Use the air-blow the preheat the IC for about 5 seconds, then heat with the nozzle until the IC remove lifts the part from the board. Samsung Electronics...
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A digitizing oscilloscope which can measure more than 100MHz High Voltage Probe A high voltage probe which can measure about less than 10KV DCU (Diagnostic Control Unit) DCU can be supplied from Samsung which can easily shows the engine’s error status Table 3-4-1 Equipment List Model...
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THV(-) ON THV(+) REFERENCE ON BIAS ON LSU ON PICK UP ON CHECK PAPPER EMPTY SENSOR CHECK FEED , EXIT SENSOR CHECK COVER SENSOR FUSER ON HOT BURNING CLEANING PRINT CHECK THV ON DUTY THERMISTER II CHECK FAN ON Samsung Electronics...
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3. Replace OP1, OP3 on the engine board. 4. Check the fuser roller for any dirt. If dirty, clean the roller. 1. Check for U205 on the engine board. 2. Replace LSU. 3. Measure the resistance at R62 and R8. If abnormal, replace them. Samsung Electronics...
Many of the parts are held in place with plastic latches. The latches break easily; release them carefully. To remove such parts, press the hook end of the latch away from the part to which it is latched. Samsung Electronics...
1. Press the cover open switch and raise the 3. Pull the roller slightly to the right to release the printer cover. left end of the roller, then take it out. 2. Use a phillips screwdriver to release the right end of the roller. Samsung Electronics...
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2. Remove one screw. Slide the shield cover in the direction of OPEN arrow marked on the cover, then remove the cover. 4. Remove three screws securing the board and pull the board out of the printer. Samsung Electronics...
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4 Remove three screws from the board, and printer cover. remove the board. 2 Remove two screws, unlatch the panel cap, then remove it. 5. Remove the Window LED and button panel LED. 3. Unplug one connector from the panel board. Samsung Electronics...
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Push the solenoid if you have difficulty to remove 2. Remove one ground screw. the pickup assembly. 4. Check the pickup rubber wear. If the rubber is heavily worn, replace it with a new one. Squeeze this tab to remove the rubber. Samsung Electronics...
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Disassembly and Reassembly 4-6 MP (Multi-Purpose) Tray 1. Open the MP tray. 3. Rotate the MP tray upward to a 45 angle to unlatch the both ends of the tray, then take it out. 2. Release two stoppers. Samsung Electronics...
3. Open the printer cover, and remove two screws. 7. Slide the main cover upward, out of printer. Note that the power switch is properly released when you remove the cover. Samsung Electronics...
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3. Remove three screws, and remove the LSU. Then unplug two connectors from the LSU. -Controller Board (see page 4-3) -MP Tray (see page xx) -Main Cover (see page 4-6) 2. Remove two screws securing the fuser cover, and remove the fuser cover. Samsung Electronics...
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2. Remove three screws, and remove the bracket. 5. If you want to remove the exit rollers, sqeeze the bottom of roller and take it out. 3. Remove two screws, unlatch the exit tray and take it out. Samsung Electronics...
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Unplug one connector from the board. 6. Remove the motor assembly. Remove two screws securing the motor to the motor bracket, then take the motor out. 4-10 Samsung Electronics...
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Unplug one connector from the board. -Controller Board (see page 4-3) -Main Cover (see page 4-7) -MP Tray (see page 4-6) 2. Unplug four connectors. 4. Remove three screws, and remove the MP plate assembly. Samsung Electronics 4-11...
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-Main Cover (see page 4-7) -MP Tray (see page 4-6) 2. Remove three screws, and remove the bracket. Exit Actuator 5. Remove four screws, and remove the fuser assembly. 3. Remove two screws from the SMPS bracket. 4-12 Samsung Electronics...
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Note: When you reassemble the halogen lamp, make sure that it is inserted into the slot properly. 2. Remove one screw, then take the thermistor out. Note: When you reassemble the thermistor, make sure that it puts in place. Samsung Electronics 4-13...
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2. Unplug two connectors from the drive board. Snap fit To replace the damper gear on the MPF assembly : 1) Remove one screw, then remove the damp gear. 3. Remove five screws, then remove the MPF assembly. 4-14 Samsung Electronics...
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5) Unlatch the PE sensor, then take it out. 2) Rotate the right end of the knockup plate until it is released, then take it out. 6) Remove two screws from the MP bracket, then remove the solenoid. 3) Remove two screws. Samsung Electronics 4-15...
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2) Pull the pickup holder to the left and rotate it until the both ends of the holder are properly released, then pull it up. 5) Remove the holder pad. 3) Remove the pickup pad using a proper tool. 4-16 Samsung Electronics...
Fuser’ and unplug four connectors. 3. Remove one screw from the engine board. 6. Remove one ground screw. 4. Turn the printer over. Remove six screws from the left and the right base brackets, and take them out. Samsung Electronics 4-17...
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8. While you push the stopper to release the PCU shield, take the PCU shield out of the printer. To replace HV terminals : Remove the terminals. Stopper HV terminals Note: When you replace with new ones, be careful that they are inserted in place. 4-18 Samsung Electronics...
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Take the sensor out while you push the both ends of the sensor. To replace the paper empty sensor : Take the sensor out while you push the both ends of the sensor inward. Paper empty sennsor Samsung Electronics 4-19...
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M3 x 8 2. Turn the unit over, and remove the actuator. To replace the PTL module : Release the three tabs latching the sensor using a phillips screwdriver, then push the sensor down. 4-20 Samsung Electronics...
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Release each tab latching the left and right holder, then push the holder down. To replace the thermistor assembly : Remove one screw, and remove the thermistor assembly. Note: When you reassemble the thermistor assembly, make sure that it puts in place. Samsung Electronics 4-21...
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-Controller Board (see page 4-3) -Main Cover (see page 4-7) -MP Tray (see page 4-6) -Engine Board (see page 4-17) 2. Remove one screw, then remove the ICU shield. 3. Remove two screws securing the sensor to the main frame. 4-22 Samsung Electronics...
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4-16 ROM 1. Press the cover open switch and raise the 3. Replace ROM using the specified jig. printer cover. Note: When you install a new ROM, be careful for the direction. 2. Remove the ROM cover. Samsung Electronics 4-23...
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Disassembly and Reassembly Memo 4-24 Samsung Electronics...
2. Transfer roller 3. Charge roller Cause 1. Defective develop roller or bad blade of toner cartridge. 2. Defective transfer roller or charge roller. Solution 1. Replace the toner cartridge, if defective. 2. Replace the roller defective. Remark Others Samsung Electronics...
3. Open rear cover and check ribs in the fuser for contamination. Clean if necessary. Remark Use LSU cleaner dated after January 1997. Others If white streaks occurs fewer than 5 or 6 times, it can be considered as normal. Samsung Electronics...
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31.3 mm = Supply roller 94.2 mm = OPC drum 46 mm = Develop roller non periodical = Blade Solution 1. Check all voltages, and adjust as necessary. 2. Check for terminal contacts, and replace the cartridge, if necessary. Remark Others Samsung Electronics...
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Repeat 2 or 3 times. Run the self-test. If the same problem persists, replace the developer. 2. Clean the rollers. If problem persists, replace the Developer. 3. The transfer roller guarantees 50,000 sheets printing. If the roller’s life is expired, replace it. Remark Others Samsung Electronics...
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2. In low temperature, wait 30 minutes after printer is powered on before you start printing. 3. Check if the hopper gear is visible from the side of the developer. If not, replace the developer. 4. Check for the supply roller contact and the supply voltage. Remark Others Samsung Electronics...
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Remark Check the charge voltage (MHV) at : U201; while operating, #10/#9 2.5~2.9V, #8 5.5~8.5V while idling, #9 2.7V, #10/#8 0V Q201 operating voltage; Base 2~2.5V, Emitter 0~1V, Collector 30~60V U203; #1 0V input, #2 0V output Others Samsung Electronics...
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2. Check if contrast mode is set to ‘Light’. If not, change the install position of the printer or attach OPC cover sheet (P/No: JC72-49093A). Remark Bias and supply voltage check point: U203; #9 pulse input, #8 pulse output Others Samsung Electronics...
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(Perform DCU diagnostic code ‘04’ to measure the voltage). Solution 1-1. Check the following parts : U201(KA324), Q204(D526-Y), T204, U203 (SN7407N), resistors, diodes in the output and feedback area. 1-2. Refer to the following information. U203(7407N)’s pin #1; pulse input, pin #2; pulse output. Remark Others Samsung Electronics...
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U201(KA324), Q204(D526-Y), T204, U203 (SN7407N) resistors, diodes in the output and feedback area. 1-2. Refer to the following information. U203(7407N)’s pin #9; pulse input, pin #8; pulse output. 1-3. Check developer contacts for contamination by toner particles. Remark Others 5-10 Samsung Electronics...
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2. The toner level is not even on the developer roller due to the bad blade. Solution 1. Replace defective holder or springs. Adjust the transfer voltage. 2. Replace the developer cartridge. Remark Others Samsung Electronics 5-11...
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1-3. Refer to Error Codes 1-090 and 1-091. 2. Use a recommended type of recording paper. 3. If the printer is under abnormal ambient condition for a long time, print errors may occur. Improve the operating environment. 4. Replace the toner cartridge. Remark Others 5-12 Samsung Electronics...
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2. After replacing the transfer roller, make sure the transfer voltage is normal. 3. Use a recommended type of recording paper. 4. Check for the PTL operation, and if required, check for the main board. Remark Others Samsung Electronics 5-13...
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1. Abnormal low temperature and humidity. In this case, ghost occurs on the entire page and the print density is too light. Solution 1. If the operating temperature and relative humidity are too low, try waiting about 1 hour after power on before using printer. Remark Others 5-14 Samsung Electronics...
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U201(KA324), Q207(A708), Q202(KSD526-Y), T201, U203 (SN7407), resistors, or diodes in the output and feedback area. Remark Others In case of no minus transfer output voltage, image quality may be poor, and background may occur in the printing. Samsung Electronics 5-15...
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1. Select ‘Thick Mode’ on paper type menu from software application to print on card stock or transparencies. 2. If the transfer voltage in the engine board is out of specification, refer to Error Code 1-091 Remark Others 5-16 Samsung Electronics...
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Solution Open the rear cover and check if the heat roller is stained. If stained, disassemble the fuser and clean the rollers with soft cloth dampened with alcohol. If ghost still occurs, replace the fuser. Remark Others Samsung Electronics 5-17...
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2. Abnormal transfer voltage or bad contact of the transfer roller Solution 1. Measure the weight of the developer and replace if the weight is less than 960g +/-20g. 2. Check the supply voltage and adjust if necessary. Check for the contact. Remark Others 5-18 Samsung Electronics...
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3-2. Measure the transfer voltage. If the voltage is abnormal, disassemble the main board and clean the components stained with toner or paper particles. 3-3. Measure the weight of the developer. If the weight is less than 960 g ±20 g, replace the developer. Remark Others Samsung Electronics 5-19...
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1. Clean the unit thoroughly. If problems still occurs, replace the developer. 2. If the roller is shorter than the recording paper or the roller is severely stained, replace the roller. 3. Clean the contaminated components. Remark Others 5-20 Samsung Electronics...
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1. Transfer roller is contaminated. 2. Abnormal (+) (-) transfer voltage, or cleaning voltage. 3. Defective transfer roller Solution 1. Clean the transfer roller thoroughly. Replace if contaminated severely. 2. Adjust the voltages. 3. Replace if necessary. Remark Others Samsung Electronics 5-21...
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1. GND OPC is not well grounded. 2. Seal tape is not removed. 3. Low toner Solution 1. Repair or replace the GND terminal. 2. Remove the seal tape. 3. Shake the toner cartridge and print. Or replace with new one. Remark Others 5-22 Samsung Electronics...
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2. If blank page is printed one time or continuously, check that the video controller oscillates properly at 47.7789 MHz. (lower than 0.75V, higher than 3.5V) 3. If blank pages prints continuously when the printer turns on, check the CPU works properly, and replace if defective. Remark Others Samsung Electronics 5-23...
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3. Defective CPU in the video controller. Solution 1. Check that the port and related parts are properly connected or soldered. 2. Check the oscillators (47.7789 MHz, 50MHz) on the video controller. 3. Replace the CPU on the video controller. Remark Others 5-24 Samsung Electronics...
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When printing on xerographic paper from cassette, the printed image is diffused. Check Engine board Cause Defective the fuser (Heat lamp) control circuit in the engine board. Solution Refer to solution 2-1 under Error Code 3-011. Remark Others Samsung Electronics 5-25...
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1-1. Select ‘Thick Mode’ on paper type menu from the software application to print on card stock or transparencies. 1-2. Check the fuser control circuit. Refer to Solution 2-1 under Error Code 3-011. 2. Check the transfer voltage and adjust if necessary. Remark Others 5-26 Samsung Electronics...
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2. Reassemble or replace the LSU. Reassemble or replace the pick-up ass’y. Reassemble or replace the defective mechanical parts. (for example, Bracket-dust). 3. Replace the solenoid. Check OP1. Check the Vedio Controller or its connection. Remark Others Samsung Electronics 5-27...
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0.7V. One side of R15 in OP1 transmitter should be 5V, and the other end 1.2V. If normal, check OP1 receiver. If not shorted, replace CPU. 3. Replace the cassette, if damaged. Remark Others 5-28 Samsung Electronics...
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1-2. Check OP contacts. In operating mode, U6 (74HC245) pin#13 should be below 0.7V. If not, check OP3 contact resistance. Replace OP3 if over 100 ohms. If the switch works normally, check R30. If defective, replace the exit sensor actuator. 2. In case of multi feeding, refer to Error Code 2-050. Remark Others Samsung Electronics 5-29...
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1-2. Check the exit sensor OP3 contact and related parts. Refer to Error Code 2-030. 2. If the paper is stuck in the fuser, disassemble the fuser and remove the jammed paper, and clean the surface of the pressure roller with soft cloth, dampened with alcohol. Remark Others 5-30 Samsung Electronics...
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2. If the clutch works properly, but the armature does not engage the pick-up housing in the pick-up ass’y, bend the armature to pick up properly. Remark The feed clutch spring has 40 turns. A pad is attached to solenoid yoke, the armature angle is 90 degrees. Others Samsung Electronics 5-31...
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2-2. Check the overheat circuit. When U5 pin 7 is below 0.5V, the overheat circuit should activate and the lamp turns off. In normal mode, pin 6 is approximately 2.6V, pin 5 is over 2.6V, and pin 7 is over 4V. If not, check all related parts. Remark Others 5-32 Samsung Electronics...
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2-3. Replace PC151 if pin 4 and 6 are short. 2-4. Replace Q101 if T1 and T2 are short. 3. Check if the overheat circuit works properly : Refer to the solution 2-2 under ‘Error Code 3-010’. Remark Others Samsung Electronics 5-33...
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(2) When you press UP key with DCU code ‘05’, if ON and OFF lamps do not turn on, check CPU pin 28 and 41, and their related parts. Normally pin 28 is over 3.5V when high, and below 0.7V when low. If the transformer works normally, replace CPU. Remark Others Q3, U3, CN3, SW151 5-34 Samsung Electronics...
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2-2. One end of R24 in the transmitter of OP2 should be 5V, and the other end 1.2V. 2-3. If the related resistors are good, check for short circuit of OP2 receiver. If OP2 is normal, replace U6 (74HC245). Remark Others Samsung Electronics 5-35...
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2-2. Check D4 anode when SW151 is pressed. D4 anode will be below 3.5V when SW151 is open. Check for R38 and R39, and replace if defective. 2-3. If D4 anode is over 3.5V, check if CPU pin 48 is short. If not, replace CPU. 3. Replace the defective actuator. Remark Others 5-36 Samsung Electronics...
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-If all are normal, check CPU pin 55. If OK, replace CPU. 2-2. Check for X1 oscillation (6.94407MHz). 2-3. Replace EPROM in the engine board, if defective. 2-4. If all above are OK, replace CPU. Remark Others U4, U202, Q9 Samsung Electronics 5-37...
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Troubleshooting Error code 3-060 Fault Memory Overflow Model ML-6100 Description When printing, error message is printed out. Check Control board Cause Insufficient printer memory. Solution Install optional SIMM memory in the control board. Remark Others 5-38 Samsung Electronics...
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2-2. With DCU code ‘00’, check for pulse at U1 pin 8 and pin 13. Or, check the related parts. 2-3. With DCU code ‘00’, check U1 pin 4 and pin 17 are over 4V. If the pins are below 1V, check R424. 2-4. If all above are OK, replace U1. Remark Others Samsung Electronics 5-39...
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2. Foreign materials in the fuser gear or developer Solution 1-1. Replace the LSU, if defective. 1-2. Check the main motor bracket or its wiring harness. 1-3. Check pick-up ass’y rolls. 2. Reassemble or replace the fuser and developer if defective. Remark Others 5-40 Samsung Electronics...
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3. Check F151 on the engine board. If open, measure the resistance between 5V and ground. If it is below 50 ohm, it is short. 4. Check F101 on the engine board. If open, check also : - R114 open - Q102, D-S, G-D, or G-S short - Defective BD101 Remark Others Samsung Electronics 5-41...
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1. For LSU, +24V supply is unstable in the engine board. 2. Difference according to LSU vendors Solution • Check the capacitor between CN 3 pin 5 and +24V is 100nF. • Check the resistor R63 (12.1Kohm). • Replace LSU. • Replace the main board. Remark Others 5-42 Samsung Electronics...
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2. LSU error 3. Bad connection between engine board and control board. Solution 1. Replace the fuser. 2. Replace the LSU. 3. Check the wiring between the engine board and the control board. 4. Replace engine board. Remark Others Samsung Electronics 5-43...
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Fault Jitter Model ML-6100 Description When printing, image is irregular. Check LSU, Motor bracket Cause 1. LSU hexahedron period 2. Defective motor bracket gears Solution 1. Replace the LSU. 2. Replace the motor bracket ass’y. Remark Others 5-44 Samsung Electronics...
6-14 Pick-Up Parts List 6-15 Cassette Exploded View 6-16 Cassette Parts List 6-17 Second Cassette Frame Exploded View (option) 6-18 Second Cassette Frame Parts List (option) 6-19 Second Cassette Exploded View (option) 6-20 Second Cassette Parts List (option) Samsung Electronics...
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Exploded Views and Parts List 6-8 MP-Tray/MPF Parts List 6-8-1 MP-Tray Parts List Ass’y Name Ass’y Code Part Name Sub Code Q’ty MEA RACK-MP TRAY JC97-01202D PMO-COVER_MP JC72-41377D PMO-TRAY_MP,A JC72-41378B PMO-TRAY_MP,B JC72-41379B PMO-TRAY_MP,C JC72-41380B PMO-ADJUSTER_P SIDE JC72-41381B PMO-LOCKER_MP JC72-41398A IPR-GUIDE LATCH JB70-10906A Samsung Electronics...