Lexmark C760 Service Manual
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Diagnostic information2-135 5060-4xx Low image density Note: If all colors have a low image density problem set the Print Darkness to High from the user’s menu. If only one color has a problem, go to “Step A.” If all colors have a problem, go to “Step B.” Step A Step B 2Print cartridge(s) - Enter the Diagnostics Mode. Remove one print cartridge at a time and run a Test Page to isolate the faulty print cartridge. Have you isolated the failing print cartridge? Replace the “Cartridge contact assembly for the failing color on page 4-29 . Go to step 3 3Reseat the ITU. Do the marks/lines persist? Go to step 4 Problem solved 4Does the printer display an 83 ITU Maintenance message? Recommend the customer order the ITU maintenance kit. See “Scheduled maintenance” on page 6-4 .Replace the “ITU assembly” on page 4-44 . Step Action and questions Yes No 1 Print cartridge - Make sure the print cartridge is seated correctly. Is the print cartridge seated correctly? Go to step 2 Install the print cartridge correctly and recheck 2The print cartridge may be out of toner. Try a new print cartridge. Does a new print cartridge fix the problem? Problem solved Replace the “Transfer HVPS board” on page 4-73 Step Action and questions Yes No 1 Make sure that color calibration has not been disabled in the Diagnostics menus, especially if the printer has been previously serviced. Was color calibration disabled? Set Color Calibration on Go to step 2 2Toner density calibration - Run toner density calibration from the Utility menu. Does this fix the problem? Problem solved Replace the “Transfer HVPS board” on page 4-73 Step Action and questions Yes No
2-136Service Manual 5060-4 xx Poor color alignment Transparency print quality is poor Step Action and questions Yes No 1 Print cartridge - Make sure that the print cartridges are properly inserted and are seated properly in their respective V blocks. Are the cartridges seated correctly? Go to step 2 Install the cartridge(s) correctly 2Front cover and cartridge contact block - Check the front cover and the cartridge contact block to make sure that all the springs and cartridge hold downs are present and correctly installed. Are all springs and cartridge hold downs present and correctly installed? Go to step 3 Replace any missing or damaged springs or hold downs 3ITU - Make sure that the ITU legs are properly seated onto the rail at the right side of the printer. This is visible by removing the yellow print car tridge. Is the ITU seated correctly? Alignment - Enter the Diagnostics Menu. Perform the alignment for the color required. See “ALIGNMENT MENU” on page 3-15 . Reinstall the ITU. If the problem continues, replace the “ITU assembly” on page 4-44 Step Action and questions Yes No 1 Transparencies - Check the media type and transparency in use. Are the recommended transparencies and media type used? Go to step 2 Inform the customer 2Is the quality of the transparency poor or do brown colors appear when projected? Go to step 3 Go to step 4 3Fuser settings - From the Diagnostics Menu select fuser settings and set to high. Does this fuser setting fix the problem?Problem solved Replace the “Fuser assembly” on page 4-35 4Does the transparency have a splotchy appearance? Go to step 5 Replace the “Second transfer roll” on page 4-71 5Transfer setting: High - From the Diagnostics Menu set Transfer setting to High. Does this transfer setting fix the problem?Problem solved Go to step 6 6Transfer setting: Low - From the Diagnostics Menu set Transfer setting to Low. Does this transfer setting fix the problem?Problem solved Replace the “Second transfer roll” on page 4-71
Diagnostic information2-137 5060-4xx Negative ghosting or faded image The print has a negative ghost on the page or the image is faded, particular with text. This problem may happen with any color and can be mistaken as toner smudges on the page. Residual image If only one color has a residual image repeated every 95 mm, replace the print cartridge. If all colors have a residual image 147 mm from the top of the page, replace the fuser assembly. Note: Do the following steps before you replace the fuser assembly: 1.Check Media Type setting on the operator panel. If the setting is for light paper, select the correct setting for the current media type. 2.If the problem continues, set the fuser temperature selection to High. 3.If the problem continues, check the page count. If the page count is greater than 200K copies and the fuser has not been replaced, advise the customer to install a new fuser CRU or a maintenance kit. If only one color has a residual image problem, go to “Horizontal lines or streaks” on page 2-134 . If all colors have a residual image problem, go to “Residual image” on page 2-137. Uneven printing If all colors have uneven print, replace the ITU assembly. The uneven print may appear as spots or streaks that are different on each page. The most likely cause for this type of problem is damage to the ITU belt in the ITU assembly. Replace the “ITU assembly” on page 4-44 . If only one color is missing or printing uneven, go to step 1. Step Action and questions Yes No 1 Check the bellcranks of the color that is having the problem. Is a bellcrank broken or missing? Replace the broken or missing bellcrank. Got to step 2 2Check each of the springs that attach to the bellcranks to make sure they are attached and not broken or missing. Are the springs for the color having the problem missing or unattached? Repair or replace the spring as necessary. Look for any signs of missing or damaged parts in the area of the color having the problem, including the ITU. Step Action and questions Yes No 1 Print cartridge - Make sure the cartridge is seated properly and that all packing material has been removed from the cartridge. Has all packing material been removed? Is the cartridge seated correctly? Problem solved Go to step 2 2Cartridge check - the cartridge may be out of toner or have another toner problem. Try a new toner cartridge. Does a new toner cartridge fix the problem? Problem solved Call your next level support
2-138Service Manual 5060-4 xx Toner smears or rubs off the page with no error code displayed Note: This type of problem is associated with improper fusing or incorrect settings for media type being used. Smudged or distorted images on fused page Step Action and questions Yes No 1 Media settings - Check to see if the printer is set for light paper. Is the printer set for light paper? Set the printer for current media type and go to step 2Go to step 3 2Does resetting the media type fix the problem? Problem solved Go to step 3 3Fuser settings - Set the fuser to High in the CE menu. Does setting the fuser to High fix the problem? Problem solved Replace the “Fuser assembly” on page 4-35 Step Action and questions Yes No 1 Remove the ITU assembly and check for any signs of debris near the paper feed reference edge mechanism underneath the ITU assembly. Are there any signs of any debris in this location? Remove the debris Go to step 2 2Check for any signs of debris on the surface of the ITU belt near the toner patch sensor (TPS) which is the white egg shaped device located on the front left corner of the ITU assembly. Note: When toner cartridges are replaced, small pieces of plastic may drop off of a toner cartridge and be deposited on the ITU belt. Are there any debris in this location?‘ Remove the debris Look for any signs of damage to the ITU belt. If found, replace the ITU assembly.
Diagnostic information2-139 5060-4xx Toner is on the back of the printed page Do the following steps before proceeding with this service check: 1.Enter the Diagnostics Mode. 2.Select Print Test , Tr a y 1 , Continuous from the menu. 3.Run at least 20 pages of text and see if the problem remains. If toner is still on the back of the printed page, proceed with this service check. If the problem is on the top two inches of the page replace the second transfer roll. If the toner is “stringy” over the top half of the page, go to step 1. Light lines or streaks appear on the page Single color streaks outside the printed page are most likely caused by a problem in the print cartridge. Replace the print cartridge. All the colors streaking at a different spot on each page is probably caused by a damaged ITU assembly. Replace the “ITU assembly” on page 4-44 . If only one color streaks in the printed area, go to step 1. Step Action and questions Yes No 1 Media settings - Check to see if the printer is set for light paper. Is the printer set for light paper? Set the printer for current media type and go to step 2Go to step 3 2Does resetting the media type fix the problem? Problem solved Go to step 3 3Fuser settings - Set the fuser to High in the CE menu. Does setting the fuser to High fix the problem? Problem solved Replace the “Fuser assembly” on page 4-35 Step Action and questions Yes No 1 Print cartridge check - Try a new print cartridge. Does a new print cartridge fix the problem? Problem solved Go to step 2 2Printhead check -The printhead lens may be contaminated by toner. Check for any signs of contamination on the lens of the printhead. Is the printhead contaminated?Go to Clear the printhead lens with a soft, lint- free cloth. Call your next level support
2-140Service Manual 5060-4 xx White streak in color plane A white streak appears in one particular color plane. This problem may be caused by a contaminated developer roll in the print cartridge. Paper wrapped around the second transfer roll Step Action and questions Yes No 1 Check to see which color is having the problem and go to step 2. 2If another cartridge is available, try a new cartridge for the color having the problem. Do you have another cartridge to try? Go to step 3 Go to step 4. 3Does a new cartridge fix the problem? Problem solved Go to step 5 4If another cartridge is not available, break the corresponding tabs off the cartridge in question as well as an adjacent color. The tabs are used to ensure that the cartridge is installed in the correct color station. Switch the two cartridges and print out a print sample to see if the streak stays with the cartridge and not the station. Does the streak change when you switch cartridges?Replace the defective cartridge. Go to step 5 5Printhead check -The printhead lens may be contaminated by toner. Check for any signs of contamination on the lens of the printhead. Is the printhead contaminated? Go to “Printhead removal and adjustments” on page 4-60 Call your next level support Step Action and questions Yes No 1 Some media can get wrapped around the second transfer roll and can affect print quality. Is there a piece of media wrapped around the second transfer roll? Remove the piece of media and go to step 2. Problem solved 2Run several pages to see if the media wraps around the second transfer roll, again. Does the media wrap around the second transfer roll, again? Replace the second transfer roll. If this does not fix the problem, call your next level of support for assistance.Problem solved
Diagnostic information2-141 5060-4xx Second transfer roll service check Note: The second transfer roll is 51.03 mm (2.009 inches) in circumference. Any print quality problems such as lines that are spaced apart indicate you should check the second transfer roll for damage, toner, or foreign material. Note: The second transfer roll is also part of the maintenance kit and should be replaced when a “83 ITU Maintenance” message appears. Ask the customer if they have replaced the second transfer roll recently. Note: If any of the following problems occur, go to “Print quality service check” on page 2-130 : A problem with only one color) Light or very light print CAUTION: Make sure the printer is powered off before making any checks on the second transfer roll or associated parts for personal safety and to prevent damage to the printer. Step Actions and questions Yes No 1 Second transfer roll assembly - Check the second transfer roll for any signs of toner buildup, surface damage to the roll, oil, or other contaminants on the surface of the roll. Do you see any problems with the second transfer roll? Replace the “Second transfer roll” on page 4-71 Go to step 2 2Transfer arms, springs, and associated hardware - Call your next level of support. None of these parts are service related parts. Is there any problem with the associated hardware? Call your next level support Go to step 3 3Transfer high voltage power supply, HV wiring, and contacts - Check the second transfer cable (transfer HVPS contact to the second transfer roll rear arm contact) for correct installation. Is the cable installed correctly? Go to step 4 Install the cable correctly 4Check the continuity of the second transfer cable. Is there continuity? Replace the FRUs in order: 1) “Second transfer roll” on page 4-71 2) “Transfer HVPS board” on page 4-73 . If this does not correct the problem, go to step 5. Replace the second transfer cable 5Make sure the ITU bias spring is not broken or missing for the color(s) that is having transfer problems. Is the ITU bias spring broken, off, or missing? Repair as necessary Go to step 7 6Check the transfer HVPS to ITU HV transfer terminal for the color(s) that is having transfer problems. Is the cable disconnected or broken? Reinstall or replace the cable Go to step 7
2-142Service Manual 5060-4 xx Tray 1 service check Tray 1 does not stay seated or fit correctly in the printer, the media fails to feed correctly from tray 1 or tray 1 is difficult to install The Tray 1 Feed Test in the Diagnostics Menu can be used to help isolate problems with paper feeding from Tray 1. 7Transfer terminal contact assembly and ITU transfer bellcrank - Check the transfer terminal contact, transfer cable, and ITU transfer bellcrank assemblies to make sure they are installed correctly, not loose, or broken. Are there any problems with the transfer terminal contact, transfer cable connection, or ITU transfer bellcrank assemblies?Repair or replace as necessary. If this does not correct the problem, contact your next level support. Replace the FRUs in order: 1) “Transfer HVPS board” on page 4-73 2) “Second transfer roll” on page 4-71 3) “ITU assembly” on page 4-44 Step Action and questions Yes No 1 Check the following parts in Tray 1 for broken or missing parts. Tray bias spring loose or missing Tray bias bellcrank Are any parts broken, loose, or missing? Repair or replace parts as necessary Go to step 2 2Make sure the autocompensator has fully retracted to its upper position. Does the autocompensator retract correctly? Go to step 3 Go to “Autocompensa tor service check” on page 2-107 3Check for any signs of damage to the paper tray guide. Is the paper tray guide damaged, loose or missing? Replace the paper tray guide. Go to step 4 4Check the following parts for wear, damage, or missing parts. Wear strips Restraint pads Wear clip Side restraint Back restraint and back restraint latch Are there broken, worn, or missing par ts? Repair or replace parts as necessary Go to step 5 5Check to make sure that the tray is correctly actuating the paper size switches on the paper size sensing board. Does the tray correctly actuate the paper size sensing switches? Go to step 6 Go to the “Tray 1 paper size sens- ing service check” on page 2-143 6Check for any signs of damage to the tray that might prevent it from actuating the switches. Is there any problem with the tray? Replace the tray assembly Go to step 7 Step Actions and questions Yes No
Diagnostic information2-143 5060-4xx Tray 1 paper size sensing service check The printer does not sense the size of the media installed in Tray 1. Note: If there is a problem when installing Tray 1, Tray 1 is difficult to remove or does not stay locked in position, go to “Tray 1 service check” on page 2-142 . Warning: Whenever the paper size sensing board is removed, customer settings in the NVRAM may be lost. The“Motor Detect” on page 3-17 must be performed if the NVRAM contents are lost during the replacement of a paper size sensing board. 7Check to see if there is anything in the printer that might be interfering with the tray being correctly installed. Is there anything in the printer that might cause the tray from installing correctly? Repair as necessary Replace the tray assembly. Step Action and questions Yes No 1 Make sure tray 1 is installed and seated correctly in the printer. Is the tray correctly installed? Go to step 2 Install tray 1 correctly. If there is still a problem, go to “Tray 1 service check” on page 2-142 . 2Is another 500-sheet tray available? Go to step 3 Go to step 4 3Try another 500-sheet tray in place of the internal tray 1 paper tray. Does this fix the problem? Go to step 4 Go to the “Tray 1 paper size sensing service check” on page 2-143 . 4Check tray 1 for broken parts, especially the teeth on the back restraint. Is the back restraint broken or any of the teeth broken or missing? Replace the back restraint Replace the tray assembly. Step Action and questions Yes No