Lexmark E 450 Dn Service Manual
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Diagnostics information2-15 4512-630 Symptom tables POST symptom table Note: Investigate any displayed codes before proceeding with these symptoms. For example, a missing toner cartridge will prevent POST from completing.Symptom Action The main motor, cooling fan, and fuser do not come on.See “Cover interlock switch service check” on page 2-18. POST completes, but LCD does not appear to be working.See “Operator panel service check” on page 2-21. Main motor does not come on. See “Main motor service check” on page 2-20. Fan does not come on. See “Cooling fan service check” on page 2-18. Fuser does not cycle. See “Fuser service check” on page 2-19. Fuser does not turn on and off. See “Fuser service check” on page 2-19. The paper feed picks and tries to feed media. See “Paper feed service checks” on page 2-21.
2-16Service Manual 4512-630 Printer symptom table Symptom Action Dead machine (no power). See “Dead machine service check” on page 2-19. Fan noisy or fan not working. See “Cooling fan service check” on page 2-18. Fuser parts melted. See “LVPS/HVPS service check” on page 2-20. Toner not fused to the media. See“Fuser service check” on page 2-19. Paper jams. See “Paper feed service checks” on page 2-21. Main motor noisy or not moving. See “Main motor service check” on page 2-20. Media skew. See “Paper feed service checks” on page 2-21. Printer not communicating with host. See “Parallel or USB port service check” on page 2-23. Front access cover will not close. See “Cover interlock switch service check” on page 2-18. Operator panel button not responding. See “Operator panel service check” on page 2-21. Operator panel lights are off or very dim. See “Operator panel service check” on page 2-21. Blank page. See “Blank page” on page 2-24. Black page. See “Black page” on page 2-25. Heavy background. See “Heavy background” on page 2-25. Light print. See “Light print” on page 2-27. White or black lines or bands. See “White or black lines or bands” on page 2-27. Toner on back of page. See “Toner on back of page” on page 2-27. Media never picks. See “Media never picks” on page 2-22. Media feeds continuously. See “Media picks during POST and/or continuously” on page 2-21. Media wrinkled or bent. See “Media “trees,” wrinkles, stacks poorly, or curls” on page 2-23. Print quality problems • Light print • Blurred characters • Toner on both sides of media • Toner not fused • Streaks • Blank pagesSee “Solving print quality problems” on page 2-28.
Diagnostics information2-17 4512-630 Service checks Service checks which involve measuring voltages on the LVPS/HVPS (low voltage power supply/ high voltage power supply board) should be performed with the printer positioned on its back side. Note: When making voltage readings, always use frame ground unless another ground is specified. See the wiring diagram in the back of the book for more information. Controller card service check Controller card service check FRU Action Controller card assembly Warning: Do not replace the operator panel and controller card at the same time. Each card contains the printer settings. When either of these cards is new, it obtains some of the settings from the other card. Settings are lost when both are new and replaced at the same time.POST (Power-On Self Test) Note: The printer should complete POST in approximately 30 seconds. If the printer fails to display lights or activate the drive motor, fuser or fan, check the following order: 1. Power to the LVPS/HVPS 2. Power from the LVPS/HVPS to the controller card 3. Cables are plugged in correctly, especially for the operator panel. The printer will not power-up without a functioning operator panel. 4. The controller card assembly. 5. The operator panel. See “Operator panel service check” on page 2-21. Verify +24 V dc input from the LVPS/HVPS. 1. Turn the printer off. 2. Disconnect the LVPS/HVPS cable from the controller card at J19. 3. Turn the printer on. 4. Verify +24 V dc on positions 8 and 9 of the cable connector. 5. If voltage is correct, check the continuity in the other conductors of the cable. If the cable is good, check the connectors to the controller board. 6. Verify that pins 7 and 12 on both the cable and the card connector are grounded. 7. If grounds are not correct on the cable, but the cable posses continuity otherwise, check the LVPS/HVPS. 8. If the grounds are not correct on the controller card, replace the controller card. (Check with one probe on the connector pin and the other on the card’s ground plane found at each screw head.) Controller card voltage outputs Turn the printer off, and plug the LVPS/HVPS cable into J19 of the controller card. See the wiring diagram at the end of the book which identifies the voltages and grounds for a good controller card. Turn the printer off before plugging or unplugging any connectors.
2-18Service Manual 4512-630 Cooling fan service check Cover interlock switch service check Note: Make sure a print cartridge assembly is installed and the cover closes all the way, engaging the cover open switch lever. LVPS/HVPSVerify main power to controller card With the printer off, unplug the LPS/HVPS cable at J19 on the controller card. Verify grounds on pins 7, 12, and 14 for both the cable and the controller card. If any of these grounds are incorrect, check the cable for continuity. Replace the cable or the respective card as necessary. Turn the printer on with the cable still unplugged, and verify the following on the cable (controller card will not be powered): If any of the voltages are incorrect, replace the LVPS/HVPS. See “Dead machine service check” on page 2-19. FRU Action Cooling fan Make sure the fan cable plug is properly seated at J4 (controller card). Turn the printer off, and disconnect the cooling fan cable from the controller card. Turn the printer on. Within a few seconds, the controller card assembly should apply +24Vdc to pin2. • If voltage is present and the fan is not turning, replace the cooling fan. If the fan still doesn’t function, replace the controller card. • If voltage is not present, check the controller card. FRU Action Cover interlock switch Disconnect the cover interlock cable from the controller card at J6. With the printer turned off, verify continuity between cable pin 1 and pin 2 with the door closed and discontinuity with the door open. Verify continuity between cable pin 1 and pin 3 with the door open and discontinuity with the door closed. Verify discontinuity between cable pins 2 and 3 whether the door is open or closed. • If either fails, replace the cover interlock switch. • If both pass continuity, turn the printer on, and measure +5 V dc on pin 2 at J6 on the controller card. • Verify pin 3 at J6 is ground. • If voltage or ground is not present, see “Controller card service check” on page 2-17 for more information. Controller card service check (Continued) FRU Action Pins Voltage J19-8 +24 V dc J19-9 +24 V dc J19-13 +5 V dc
Diagnostics information2-19 4512-630 Dead machine service check CAUTION: Check the AC line voltage. The voltage should be within the following limits: •100 V ac (volts alternating current) — 127 V ac for the 110 V printer •200 V ac — 240 V ac for the 220 V printer Fuser service check When toner is partially fused to the media, it is usually caused by low fuser temperature. The line voltage to the printer must be within the following limits: •100 V ac—127 V ac for the 110 V model printer •200 V ac—240 V ac for the 220 V model printer This printer uses a belt fuser and therefore does not have a lamp. FRU Action LVPS/HVPSUnplug the printer. Remove the LVPS/HVPS, and check the fuses for continuity. • If open, replace the LVPS/HVPS. • If not open, check the switch continuity across its conductors with the switch on. Turn the switch off. Plug the AC line into the LVPS/HVPS and switch unit on. Note: Voltages may be exposed at several places on the board. Do these verifications, and then unplug the card: •Verify 24 V dc on pins 8, 9, and 10 at PCN1. •Verify approximately 3V on pins 1—3. •Verify approximately 5V on pins 4 and 13. •If voltages are not correct, replace the LVPS/HVPS. •If voltages are correct, check the controller card. See “Controller card connector pin values” on page 5-2. Fuser service check FRU Action Fuser power cable LVPS/HVPS FuserUnplug the printer, and disconnect the fuser cable plug from the LVPS/HVPS board connector at PCN5. Check for continuity across the fuser by checking across the connector pins. • If there is continuity, check the LVPS/HVPS. See “LVPS/HVPS service check” on page 2-20. • If there is no continuity, disconnect the fuser power cable at both ends and check each conductor for continuity. Replace cable if necessary. • If the cable tests good, replace the fuser. Make sure the fuser thermistor is correctly connected to the controller board at J13. If the problem persists, disconnect the thermistor cable and check for less than +5 V dc on pin 1. Pin 2 should be ground. If line voltage is incorrect on pin 1, see “Controller card service check” on page 2-17 for more information. Fuser Disconnect the thermistor cable from J13 on the controller card. Measure the resistance across the ends of the thermistor cable. Replace the fuser assembly if the resistance is lower than 1K ohm or shorted. Note: Resistance measures approximately 400K ohms when cool and 1K ohms hot.
2-20Service Manual 4512-630 LVPS/HVPS service check Main motor service check FRU Action LVPS/HVPSLVPS portion of board Fuses that open typically indicate a faulty LVPS/HVPS. Disconnect the power cable, and open the LVPS/HVPS enough to test the switch. The switch will show continuity across the conductors with a meter when the switch is on. If the switch is good, see “Dead machine service check” on page 2-19 for more diagnostics. HVPS portion of board Problems with the HVPS are exhibited in the print quality. See “LVPS/HVPS service check” on page 2-20 for more information. FRU Action Main gear drive Main motor cable LVPS/HVPS Controller card Warning: Do not replace the operator panel and controller card at the same time. Each card contains the printer settings. When either of these cards is new, it obtains the settings from the other card. Settings are lost when both are new and replaced at the same time.Turn off the printer, and unplug the main motor cable at J17. Turn on the printer, and check for the following voltages at J17: Verify ground at pin 5 for both the card and cable. • If these voltages are correct, check the main motor cable for continuity. - Remove the left side cover to access the connector on the motor. - If continuity exists on each wire, replace the main gear drive which includes the motor. - If continuity does not exist on one or more of the wires, replace the motor cable. • If these voltages are not correct, see “Controller card connector pin values” on page 5-2, or replace the controller card. See “Controller card removal” on page 4-13. J17 pins Voltages Pins 1—4 Approx. +3.3 V dc Pin 6 Approx. +5 V dc Pins 7—9 10 V dc—24 V dc
Diagnostics information2-21 4512-630 Operator panel service check Inspect the operator panel cable for damage. Make sure the cable is plugged in securely. Run POST, and check each light for proper operation. See “Power—On Self Test (POST) sequence” on page 2-1. Paper feed service checks Paper jam error indication during POST Media picks during POST and/or continuously LCD Operator panel service check FRU Action Operator panel (LED) Controller card Warning: Do not replace the operator panel and controller card at the same time. Each card contains the printer settings. When either of these cards is new, it obtains the settings from the other card. Settings are lost when both are new and replaced at the same time. Lights If the LCD does not come on, open the controller card cage and locate the operator panel connector at J3. Make sure the cable is properly connected to the controller card and the controller card has input voltage to it. With the printer on, verify the following without disconnecting the cable: • Pins 1, 3, 5, and 6–3.3 v • Pin 2–5 v • Pins 4 and 7–GND If these are correct and the operator panel is not functioning, replace the operator panel. If any are incorrect, see “Controller card service check” on page 2-17. Buttons If the buttons do not respond, replace the operator panel. There is no test or repair for the faulty switches. FRU Action Fuser (exit sensor) If the exit sensor flag, which is visible at the back of the fuser, is in any position other than vertical, the printer will display a paper jam. Make sure the flag is operating freely. Replace the fuser if the sensor is damaged. Input/duplex sensor Manual feed sensorMake sure the input paper feed sensors are working properly. A stuck or incorrectly installed sensor causes a paper jam indication. FRU Action ACM Manual feed clutchCheck the ACM clutch for wear. The solenoid interacts with the clutch to control the motion of the pick tires. If the ratchet teeth of the ACM clutch assembly are worn or broken, the solenoid may not stop the ACM from rotating. Replace the ACM clutch assembly if necessary. Check the manual feed clutch for damage.
2-22Service Manual 4512-630 Media picks but stops halfway through the printer Media never picks Media occasionally mispicks or picks multiple sheets at once FRU Action Input/Duplex sensors (under print cartridge assembly) Input sensor (manual)Make sure the input sensors are working properly. Check for a broken or stuck flag on the input sensors. Make sure the cables are seated on the controller card at J23 (Tray 1 input) and J20 (manual input). Check for about +5 V dc on pin 6 at J23 (Input/duplex sensors) and pin 3 at J20 (Input sensor). • If correct, replace the input paper feed sensor. • If these voltages are not correct, replace the controller card. FRU Action Paper feed (pick tires) tray 1 Paper feed (pick tires) tray 2 Media drive ASM Media feed clutch ASM Manual feed clutch ASM P/U and manual feed solenoid ACM drive shaftOpen the left cover, and verify that the solenoids and clutches are functioning when an attempt is made to feed the media. Make sure the rubber tires on the ACM are installed and clean. Replace the tires, ACM drive, clutch assemblies, solenoids, or drive shaft as necessary. FRU Action Tray 1 Tray 2 (option)Check tray for media catch points. If the sheet being fed stops momentarily, the ACM applies additional vertical force, causing additional sheets to feed. Do not mix media types in one tray. Paper pick tires (Tray 1 or tray 2)Check the tires in the ACM assembly for signs of wear or damage. Replace the tires as necessary. ACM clutch complete bill of material (CBM) Manual feed clutch CBM Media feed clutch ASM (tray 1 only) Manual feed clutch ASMOpen left cover, and observe the solenoid and clutch actions at the ACM and manual feed shafts as a print job is attempted. Replace the faulty part. Controller card P/U and manual feed solenoid ASM.Disconnect the solenoid cable at J21 on the controller card. Measure the resistance across cable pins 1 and 2 and then pins 3 and 4. • The resistance should be 180—250 ohms. • If it is not, replace the solenoid assembly. • If the resistance is 180—250 ohms, check the controller card. See “Controller card service check” on page 2-17 for more information. Replace controller card as necessary.
Diagnostics information2-23 4512-630 Media skews Media “trees,” wrinkles, stacks poorly, or curls Parallel or USB port service check 1.Perform a print test to make sure the printer prints correctly. Verify that the indicator light is on, then press to print menu settings. 2.Be sure the printer parallel cable is designed for bidirectional printing. 3.Be sure the user’s application is set up correctly. 4.If the internal print test page prints correctly, the user’s application/printer driver is set up correctly, and the correct bidirectional parallel cable is installed, but the printer still fails to print on command from the host computer, replace the controller card. 5.Check the USB cable for continuity. FRU Action Paper feed (pick tires) tray 1 Paper feed (pick tires) tray 2 Tray 1 Tray 2 (option)Check tires for debris. If tires are new, try reversing each on its hub. Check side guides on Tray 1 and Tray 2. Guides set for a full stack of media may be too wide when the stack is short. FRU Action Fuser This problem is most likely due to a worn backup roll. It causes the printer to run hotter than required for the media being printed. Excessive heat can cause media treeing problems, poor stacking, or curl. Print the menu sheet (press and release with the printer in ready mode). Look at the media settings. Some, such as card stock or rough texture, may require a higher fuser temperature, which leads to more of these problems (except stacking) in plain paper. • Change settings using the printer driver. • Use the local printer setup utility (included on the CD) to change the NVRAM settings. Try a different ream of paper. Moist media has a higher tendency to crease (treeing) and curl.
2-24Service Manual 4512-630 Print quality service checks Note: Ensure the cover closes tightly. A gap in the opening may allow light to expose the photoconductor resulting in a ‘dirty’ print. Extreme environmental conditions, temperatures, and humidity will affect the print quality. Using print quality test pages To help isolate print quality problems, like streaking, print test pages using the print quality test pages. To print the print quality test pages: 1.Enter Configuration Menu. a.Turn off the printer. b.Press and hold and . c.Turn on the printer. d.Release the buttons when Performing Self Test displays.. e.The message CONFIG MENU displays. f.Press to Prt Quality Pgs. g.Press to print the pages. Four pages print to help evaluate print quality. The first page has various fonts and a graphic, the second page is gray with graphics, the third page is black, and the last page is blank. 2.Use the test pages to isolate problems such as light or toner streaks. See “POST symptom table” on page 2-15 for solutions to these problems. 3.Press to Exit Config Menu and press . To exit configuration, turn the printer off. Blank page FRU Action Toner cartridge (not a FRU)Remove the toner cartridge, and gently shake it to evenly distribute the toner. Check for cartridge damage. Printhead LVPS/HVPS Controller card Blank pages can be caused by a defective printhead assembly, LVPS/HVPS, or controller card. • Printhead errors typically result in printer service errors unless there is blockage of the beam or dust on the lens. • Blank pages typically are caused by the PC roll not being properly charged. Try a different PC kit. Unplug the printer, and check the cable continuity between the LVPS/HVPS connector marked OPC (at PCN 2) and the corresponding wire form (spring) found about 14 mm above and to the right of the transfer roll gear. • If there is not continuity, call the next level of service. Try a different toner cartridge and PC kit. • If those fail, replace the LVPS/HVPS, controller card, or the printhead in that order.