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Basic Troubleshooting
www.get-u-wice.com
Basic Troubleshooting
For Service Master On Digital Machines
Ricoh Europe B.V. Technical Training Centre
BasicTroubleshooting_SER_ppt_EN_v1.2.a
List of Changes: (See: View > Notes Page) Date of change 25-July-2005 09-Mar-2006 Version History 1.0.a 1.1.a Description
Initial version (no changes) Slide 1: Added Digital machines Slide 51: Added arrows for feed direction Slide 58: Wording Copies replaced by Originals Slide 59: Added SMC data sheet for Jams Added slides for paper jams (chapter 6)
13-Mar-2006
1.2.a
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Basic Troubleshooting
Objectives
After this training you should: Be able to read schematics Know how to use SP modes for troubleshooting Understand process control Be able to identify and locate problems Be able to find documentation for troubleshooting
This course is designed in the following manner: There will be an overview at the beginning. To go back to this overview slide you can always click on the home button.
There will be several references to the Service Manual chapters or other documents like Operating Instructions. This is shown in the notes as:
The example explains that more information can be found in the Copy Reference Operating Instructions chapter 2 copying subchapter slip sheets.
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Requirements
Service Manual Point to Point Diagram Multimeter MFP
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Training material
This presentation
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Pre-requisites and Exam
Basic Digital Imaging for Service Master WICE Multiple choice exam
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Module overview
1. Introduction 2. Troubleshooting Tools 3. Electrical Components 4. Process Control 5. Image Quality Problems 6. Paper Path 7. Scanning 8. SP modes 9. Tips
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Basic Troubleshooting
1. Introduction
Troubleshooting is part art, part science. No check list can ever be expected to cover ALL problems you may encounter in the field. Always try to eliminate the problem. Good knowledge of the principles in your machine helps you the eliminate the problem. You need to eliminate possible causes. Initially make a list of possible causes. As the list of possible causes shrinks, the probable fault becomes more obvious. Separate the machine in modules (like scanner, transfer, fusing, finisher, controller, etc.) Be sure to look through the troubleshooting section of the machine's service manual, as well as any technical bulletin that may have been released.
1. Introduction
When troubleshooting difficult problems, you need to make sure you organize your approach. Use your knowledge of the machine to track down the cause of the problem. When all else fails, start over again and double-check your work. While this may appear as a very lengthy process, it will ultimately save time in the long run. Most problems are simple ones. Before attempting to fix a multifaceted, complex mess, always double check the basics. There probably is no need to replace all the transport rollers, when the problem is just curled paper. You will need to come up with a list of tests that you can perform, to further narrow down your options. These tests do not need to be complicated. Often you can spot the problem just by looking at the components in question. Visible scratches on the OPC drum, damaged or dirty rollers and dirty pick-off pawls are all leading indicators of trouble. Spotting any of these probably means that you have solved the problem. Make sure you have eliminated as many causes as possible before you start replacing parts. If you are unsure, you might test components by swapping them between two different machines, rather than replacing them outright. You may be tempted to just start replacing parts until the machine starts working again. While this may solve the problem, it is not cost effective. For example, check all connections before replacing a printer controller unit. While this does seem like common sense, it is sometimes easy to overlook simple concepts when you are involved in a frustrating problem.
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1. Introduction
Be careful for multiple problems occurring at the same time. Always test test test your machine.
1. Introduction
Finally, once you have fixed the problem, be sure to test the machine thoroughly. Nothing is more aggravating ( to you and your customers ) than making multiple service calls for the same problem.
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2. Troubleshooting Tools
Multimeter Testchart Schematics Service Manual SMC data Diagnostic page In/Output check Maintenance NVRAM backup Firmware RTB/ Technical Tips/ Tessa-support/ Forum* /Whiteboard* * if available
2. Troubleshooting Tools
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2. Multimeter
Most common settings
V mV A mA
Volts Millivolts Amps Milliamps Microamps
~
Alternating Current (AC) Direct Current (DC) Ohms Diodes Beeper
µA
2. Troubleshooting Tools
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2. Multimeter
A handy tool for troubleshooting
2. Troubleshooting Tools
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2. Test Chart
See the notes pages for more details.
2. Troubleshooting Tools
A: Leading edge registration (Max. A3/DLT size copier) B: Side-to- Side registration / Skew (Max. A3/DLT size copier) C: Leading edge registration (Max. A4/LT size copier) D: Side-to- Side registration / Skew (Max. A4/LT size copier) E: Jitter (Max. A3/DLT size copier) F: White line(s) in half tone area (Max. A3/DLT size copier) G: White line(s) (Max. A3/DLT size copier) H: Main scan / horizontal magnification (Max. A3/DLT size copier) I: Sub scan / vertical magnification (Max. A3/DLT size copier) J: Solid black area K: Photo image L: Scanning bit error (Max. A3/DLT size copier) N: Letter M: Uneven image density (Max. A3/DLT size copier) O: Jitter (Max. A4/LT size copier) P: Uneven image density (Max. A4/LT size copier) Q: White line(s) R: Sub scan / vertical magnification (Max. A4/LT size copier) S: Scanning bit error (Max. A4/LT size copier) T: Main scan / horizontal magnification (Max. A4/LT size copier) U: White line(s) in half tone area (Max. A4/LT size copier) V: ID balance of solid black areas W: Resolution
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2. Schematics
The schematics can help you to eliminate the problem. For example 24 volt is missing because the front door switch is not working. Schematics can be found in the Point-to-Point (P-to-P) diagrams.
2. Troubleshooting Tools
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2. Symbol Table
AC Line DC Line Pulse Signal Signal direction Active High Active Low Voltage
2. Troubleshooting Tools
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2. Component Layout
2. Troubleshooting Tools
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2. Connectors
2. Troubleshooting Tools
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2. Active High / Active Low
Active High Close the door (active): measure 24Volt Open the door (inactive): measure 0Volt
Active low Sensor detect paper (active): measure 0Volt Sensor detect no paper (inactive): measure 5Volt
2. Troubleshooting Tools
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2. Service Manual
One of the chapters of the Service Manual can be useful for troubleshooting. Troubleshooting Specifications Detailed Section Descriptions Service Manuals are also available on http://www.tessa-support.com
2. Troubleshooting Tools
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2. SMC data
Useful when checking parameters and when replacing NVRAM or do a reset. SC (Service Call) history is also printed on the SMC data sheet. To escalate problems SMC data sheet is required.
2. Troubleshooting Tools
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2. Diagnostic page
Some internal tests are done by the machine, the result is printed. A special tool is available to test the parallel port Loop back connector
2. Troubleshooting Tools
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2. In/Output check
Input check Use to check sensors, switches, etc. Output check Use to check motors, clutches, solenoids, etc.
2. Troubleshooting Tools
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2. Maintenance
Keep on track with the maintenance to prevent quality items. Old developer can not hold the toner anymore. Result dusting dirty sensors jams etc.
Bad maintenance can cause extra service calls!!!
2. Troubleshooting Tools
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2. NVRAM backup
On GW machines you can do a backup. Use for later purposes
» If NVRAM is replaced » If you reset NVRAM
Replacing boards without ESD protection can cause strange problems. Electronic distortions can change parameters stored in NVRAM.
2. Troubleshooting Tools
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2. Firmware
In some cases new firmware can solve or prevent problems. Always have firmware with you. Check the latest firmware on www.tessa-support.com
2. Troubleshooting Tools
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2. MB/ RTB/ RTT
MB (Modification Bulletin) Parts catalogue correction Service manual correction Parts modifications RTB (Ricoh Technical Bulletin) Troubleshooting items Firmware history etc RTT (Ricoh Technical Tips) See www.tessa-support.com
2. Troubleshooting Tools
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3. Electrical Components
3. Electrical Components
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3. Laser Diodes
A laser beam consists of light at one wavelength. The drum is most sensitive for a specific wave length for discharging. Check: Blank output? SC table. Interlock switches
Laser Diode
3. Electrical Components
LD Unit
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3. Thermistors
The name comes from thermally sensitive resistor. (measures the temperature of the fusing) To prevent over temperature a thermofuse or thermostat is used. Check: Use In/Output check Multimeter short or open circuit (disconnect first).
Thermistor
3. Electrical Components
The graphic shows the relation between resistance and temperature. This is typically an NTC-thermistor (Negative Temperature Coefficient) The logic of the machine uses this information to control the temperature of the fusing unit.
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3. Thermoswitches
As the name implies, a thermoswitch (also known as thermal switch or thermostat) is a temperature controlled switch. The difference between the opening and closing temperature of a thermoswitch is the "hysterisis" or "differential". In Ricoh products, thermoswitches are usually overheating safety devices with a large hysterisis. For example, the thermoswitch used in one of the scanners opens at 140ºC but will not close again until its temperature drops to -35ºC! Check: Visual fusing lamp on? Multimeter short or open circuit (disconnect first). 3. Electrical Components
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3. Micro Switches
These switches have a characteristic sound or click when the contacts close. The main advantage of a micro switch is its durability and its consistency. Check: Use In/Output check or multimeter (disconnect first). Note: when replace check which pins are used.
C (Common) NO (Normally Open) NC (Normally Closed).
3. Electrical Components
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3. Stepper Motor
Change the magnetic field by using another coil. The rotor makes one step. Often used in duplex path. Check: Is it easy to stop the motor / irregular drive?
» Yes: replace motor
3. Electrical Components
Stepper motors are used whenever accurate positioning of a component is required. The outer shell of the motor is stationary. Coils are wound around teeth attached to this shell. The rotor of the motor, made of iron, can rotate. The arrangement of the teeth is such that, if pulses are applied to the coils in the correct timing sequence, the rotor of the motor can be rotated in stepwise increments of a few degrees.
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3. Servo Motor
Often used for continuous drive such as development motor, drum motor etc. Check: Is it easy to stop the motor / irregular drive? Yes: replace motor
3. Electrical Components
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3. Torque Limiter Clutches
Torque limiter clutches (also called slip clutches) are often used in reverse rollers of feed and reverse roller paper feed mechanisms. Check: Is it easy to stop the shaft/roller? Do you see corrosion?
» Yes: replace clutch
Outer Magnet Inner Magnet Collar
Reverse Roller
3. Electrical Components
Limit Hub
A torque limiter clutch transmit rotation to a drive component (usually a roller, pulley, or gear mounted on a rotating shaft). As long as the resistance to rotation is less than the torque (twisting force) limitation of the clutch, the roller turns with the shaft. If the resistance exceeds the torque limitation, the roller stops turning--it slips. In fact, it may turn in the opposite direction if sufficient counter force is applied. Torque limiter structures vary: some use springs as slip mechanism, while others use magnetic force or powder filling. Compared to those that use springs, torque limiters that use magnets and/or powders do not need to be lubricated with grease or other lubricants, so that they are easier to maintain. Magnet-type torque limiter does not generate much heat, even after extended use, because it does not come in contact with other components. This ensures stable torque.
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3. Torque Limiter Clutches
Magnet and ferrite powder type slip clutch. Check: Is it easy to stop the shaft/roller? Do you see corrosion?
» Yes: replace clutch
3. Electrical Components
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Basic Troubleshooting
3. Electromagnetic Clutches
Gear [A] is driven by a motor. This gear is an idle gear; it does not drive the roller shaft [B]. Shaft [B] is attached to the rotatable part [C] of the clutch, and held in place by an E-ring [D]. Check Is it easy to stop the shaft/roller? Do you see corrosion?
» Yes: replace clutch
3. Electrical Components
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3. Spring Clutches
The spring grips both pieces very tightly, it act as one unit and pass on the rotation from the motor. When the sleeve is kept from turning, the spring expands away from the drive hub, disengaging the drive. Check Is it easy to stop the shaft/roller?
» Cleaning the clutch can have good results.
3. Electrical Components
The sleeve is attached to one end of the spring (the clutch spring tail). The other end of the spring is engaged with the output hub.
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Basic Troubleshooting
3. Feedback Type Potential Sensor
d
Even if distance [d] between drum (1) and sensor (2) changes, the measurement of drum surface potential is still accurate Calibration is not required Check SC table In/Output check (some machines)
Detector Gate PE element
V
Drum
Gate
Feedback circuit
3. Electrical Components
Some machines use a feedback type potential sensor. The advantages are: This type has a very high accuracy compared to the conventional type potential sensor It requires no calibration, this means you do not have to wait 5 minutes (to let the residual voltage disappear) to do forced process control self check. On older models you have to wait at least 5 minutes. Operation: An oscillator supplies an AC voltage to a piezo electric element, which causes the PE element to contract and expand with the frequency of the AC voltage. The gates will close and open the gap between the photoconductor and the detector. The detector will pickup the field of the photoconductor when the gap is big, and the field of the gate when the gap is small. The feedback circuit will change the voltage on the gate until the detector pickups no difference in field between the detector and the photoconductor. At that moment the voltage of the gate is equal to the voltage of the photoconductor. The voltage of the detector is measured then with a standard analog to digital converter. This whole process is done in milliseconds
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Basic Troubleshooting
3. ID Sensor
Black ID sensor Color ID sensor
The black ID sensor is a direct reflection sensor. It consists of an LED and a receptor. The color ID sensor uses both receptor sensors to gather light reflected from the color toner ID sensor patterns. This increases the accuracy. Check SC table Clean the sensor
3. Electrical Components
Black ID sensor The light emitted from the LED reflects directly from the bare surface of the drum or ITB to the receptor. The illustration above shows the sensor reading a toner patch on the surface of the drum or ITB. The black ID sensor output after reading the bare drum or ITB surface is Vsg. The reading of the light reflected from the toner of a developed ID sensor pattern on the drum or ITB is Vsp. Color ID sensor The color ID sensor is a combination of a direct reflection sensor and a diffuse sensor. Like the black ID sensor, the color ID sensor contains an LED and a receptor. However, the color ID sensor also has a diffuse receptor to gather additional diffuse light reflected from the colors of the ID sensor patterns. When light is reflected off the toner, it tends to scatter from the toner surface at oblique angles. The diffuse receptor is provided in the color ID sensor to gather some of this diffuse light. The color ID sensor output after reading the bare drum or ITB surface with the direct reflection LED and receptor is Vsg. The reading of light reflected from the toner of a developed ID sensor pattern is Vsp.
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Basic Troubleshooting
3. Photo-interrupters
A photo-interrupter consists of an LED and a phototransistor separated by a slot. Check: SC table Use In/Output check Clean sensor
» Swap sensors » Sensor or wire defect
Note: If replacing photo-interrupter use an identical one.
3. Electrical Components
There are many different types photo-interrupters. When replacing a photo-interrupter use the correct indicated part.
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3. Reflective Photo-sensors
Optical detection without mechanical parts. Check:
SC table Use In/Output check Clean sensor » Swap sensors » Sensor or wire defect
Note: If replacing photo-sensor use an identical one.
3. Electrical Components
There are many different types photo-sensors. When replacing a photo-sensors use the correct indicated part.
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4. Process Control
Process control is necessary to adapt the machine to the environment and drum life. Prevent background Maintain image density Process control know 2 steps: Latent Image Control
» Maintain development potential » Voltage and bias are set
Toner density Control
4. Process Control
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4. New Drum
How process control is done differs on machine type. This diagram shows the ideal relationship between drum potential and image density with a new drum.
-800V VD
VD = Drum potential with no laser power VL = Drum potential with max. laser power VB = Development bias VR = Residual voltage
white
VB
Drum Potential -130V New drum Applied Laser Power
4. Process Control
density VL
black
VR
This relationship must be maintained in order to achieve consistent copy quality during the life of the drum. But changes occur in the laser optics, charge sections and in drum sensitivity. These changes cause the relation between drum potential and applied laser power to change also. It should be noted that `max laser power' in this diagram is not the absolute max that can be got from the laser diode. It is the laser power required to get the max density (full black), and this can be adjusted
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4. Aging Drum
When the drum ages, sensitivity reduces (see the red line). As a result, the laser power applied for max density in the greyscale results in a drum potential of VL', and this gives a gray density instead of a black density. Also, the residual voltage VR increases. This cannot be compensated even if laser diode power is increased.
-800V VD' VB
white
VD
Greyscale Drum Potential -130V New drum Applied Laser Power
4. Process Control
Older drum
VL' VL
Is this supposed to be Black? Not good!
VR' VR
What is Residual Voltage? Residual voltage is the drum potential after quenching. There is always a small residual voltage, even on a new drum. The amount of residual voltage (VR) will increase during drum life. This increased VR can have a negative effect on VL even if maximum laser power is exposed on the drum the full development potential will not be reached. This means no full black density anymore.
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4. Adjustment of Vd
The new VD is too low. So, the machine increases the voltage applied by the charge roller to bring VD back up to its old value. The electrostatic potential of the old drum shifts upward as shown (see the blue line). Note that VL also shift.
-800V VD' VB Drum Potential -130V New drum Applied Laser Power
4. Process Control
white
VD After Charge Voltage Adjustment
Older drum
VL' VL VR' VR
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4. Adjustment of Dev Bias
Next, development bias is increased to compensate for the effect of increased residual voltage (Vr). The development bias is changed by the difference between VL and VL'
-800V VD' VB' VB Drum Potential -130V VD After Development Bias Adjusted
white
VL
Older drum VL New drum Applied Laser Power
VL' VL VR' VR
4. Process Control
The adjustment of the development bias achieves full black density where the drum is exposed by the laser at the maximum power for the grayscale. It also prevents dirty background on unexposed areas. The drum sensitivity is reduced, as mentioned earlier. Because of this, changes in laser power between the gradations in the grayscale are larger.
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4. Adjustment Laser Power
Finally, the laser power for maximum density on the grayscale is adjusted so that the drum potential will be VL'. This completes the potential control phase of process control.
-800V VD' VB' VB Old drum after process VD control completed After Laser Power for Max Density Adjusted
white
Drum Potential -130V
Older drum
VL' VL VR' VR
New max LD power
New drum Applied Laser Power
4. Process Control
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4. Toner Density Control
Vref is reference for new developer. New developer has a fixed concentration of toner Vref is set during initialisation when changing developer. Low density High density more toner less toner
4. Process Control
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4. Toner Density Control
The output of the TD sensor is compared with a reference voltage: Vref.
Toner Supply Clutch On Time Calculation Pixel Count TD Sensor Output (VTD) GAIN
VT Reference Voltage (V ) REF (New VREF ) VT Reference Voltage Update VREF Update ID Sensor Output (VSP/VSG) TD Sensor Initial Setting (V ) REF
Vref changes during process control, to keep the image quality.
4. Process Control
To stabilize toner concentration, toner supply amount (toner supply clutch on time) is controlled by referring to VREF and VTD. The toner supply amount is calculated at every copy. ID sensor information is commonly used for updating VREF.
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4. Tips
Background problems Check
» Lifetime developer and drum.
Reduce the interval for auto process control.
» Specially in fast changing environments.
In some cases you can increase VD.
» Be careful, this action can decrease the lifetime of the drum.
Note Changing VB effects the potential development which effects the image density.
4. Process Control
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5. Image Quality Problems
Before attempting to troubleshoot this problem, ask yourself this question: Is this a scanning problem? Is this a printing problem? Here is a quick test: Print out one of the test pages. Make a copy of the test page and compare them. If the problem only occurs with the copy, it is probably a problem with the platen glass. If it occurs on both, it is probably a printer problem. Use reduction or enlargement to see if a spot or scratch is also enlarged or reduced. If so the scanner is the problem. Also check the mirrors, lens,lamp, transport belt document feeder, etc.
5. Image Quality Problems
Scanner For problems with the scanner, examine the exposure glass. Clean off any whiteout, dust specks and fingerprints. Even if nothing is visible, try cleaning the glass regardless. If that fails, you need to consider other parts of the scanner--mirrors, optics, CCD, etc. Printer For printer problems, you need to determine where the problem occurs: Development Transfer Fusing Transport. These can often be difficult to distinguish, and you may have to closely inspect each part looking for anything unusual.
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5. Mark's on the output
Feed direction
If the mark appears in the same location on each sheet, it is probably the scanner (platen glass).
Feed direction
If the mark's position either shifts, repeats or appears intermittently, it is probably a printer problem.
Feed direction
If the mark repeats at regular intervals along the direction the paper travels, it is probably a problem with a roller. Typically, each roller has a unique diameter. Measuring the distance between the marks, determines the diameter of the offending roller. (distance = diameter x ) = 3.14 Alternatively, roll the copy until the marks line up. This will give you a tube with the diameter of the offending roller.
5. Image Quality Problems
Some machines may have OPC belts, transport belts or transfer belts which are larger than a single sheet of paper. These may cause a single mark that shifts about the paper. (Note: the mark will only shift along the direction the paper travels but never across the paper). Belts that are much larger than a single sheet of paper may only produce a mark every few sheets. For intermittent marks, make sure to run several copies in a row, noting how often the mark appears. This will give you a general idea of the belts size.
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5. Quality Items
Light Copy Check User settings (lighter density) Copy image density setting is too low. Damp or poor-quality paper. Toner is low. Low development bias. Damaged OPC Drum. Improper Toner Density. Dark or Dirty Copy Drum Grounding (shaft and springs in the drum) Check User settings (darker density) Copy image density setting is too high. Dirty optics, lenses or mirrors. Insufficient charge on the OPC drum. High development bias. No charge on the OPC drum. Broken corona wire. Faulty power unit or contacts. Scratches or damage along the length of the OPC drum. Scratches or damage along the length of the hot roller. Faulty cleaning blade. Black Lines (along the paper path) Scratches or damage running around the OPC drum. Scratches or damage running around the hot roller. Faulty cleaning blade. Dirty transport rollers. Dirty pawls. Check position Toner Shield Glass.
Black Copy
Black Lines (across the paper path)
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5. Quality Items
Black Lines (in the Sub-Scan direction) White Lines (along the paper path) Faulty elements in the CCD. Dirty corona wire. Dirty charge roller. Stained toner shield glass. Blocked doctor gap. White Spots/Deletions Moisture in the paper. Dam aged OPC drum. Dam aged hot roller. Black Spots Dirty exposure glass or optics. Dam aged OPC drum. Contam inants on the drum. Contam ination of the machine. Dam aged or dirty hot roller. Hot roller strippers. Contam inated developer or toner. Dirty drum cleaning roller. The Image Wipes Off or Smears The toner is not properly fused to the paper. The hot roller does not reach the proper fusing temperature. Faulty fusing lamp. Out of fusing oil. Faulty thermistors or thermofuses. The paper is too thick. On some glossy paper, the toner may chip off. Try using a non-glossy paper.
5. Image Quality Problems
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5. Quality Items
Latent Image/Ghosting Uneven Image Density Faulty drum cleaning blade. Faulty hot roller cleaning. Faulty quenching lamp. Uneven corona wire height. Damaged OPC drum. Uneven toner density. Machine level (slant can move the developer to 1 side). Vibration in the machine during exposure. A jar or shock to the paper as it moves through the paper path especially common with thick paper.
Jitter (dark, light or blurred bands running across the paper path these will usually be in the same location on each copy) Dark or black bands (a wide band running across the paper path) Background problems
The OPC drum has been damaged by exposing it to light for too long.
Reduce the interval for auto process control. Specially in changing environments.
5. Image Quality Problems
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5. Quality Items (Registration)
Check with test print from the machine. Check timing (in-line registration) Check side to side registration
» Each tray has it's own setting.
Check buckle (prevent skew) For each tray you can change these settings.
5. Image Quality Problems
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6. Paper Path
Unsupported Damaged
Always check the user guide for a list of paper media that is supported by the machine. It is not uncommon for paper jams to occur because incorrect paper has been used. The above illustrations are examples.
6. Paper Path
Initially you must determine whether the problem is with the paper, the paper path or the operator. Firstly inspect the paper in the tray: Has it been placed in the tray properly? Are the edges or corners damaged? Has the tray been overfilled? Does the paper have a noticeable curl? Does the edge of the paper appear to be wavy? Next, try running fresh (newly opened), high-quality paper. Does that jam as well? If you can't find a problem with the paper, start looking at the transport rollers. Make sure they're not dirty, worn, crusted, or damaged. You can also check the gear trains and any clutches. Make sure the sensors and timing switches are working properly. Even if you do find a problem with the paper, you may wish to check for other problems--particularly if the machine often jams in the same place. It is possible that the poor quality paper may just be aggravating another minor problem
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6. Paper Path
Make sure there are no paper scraps in the paper tray unit as these can also cause paper jams. Additionally transparencies and other special media may be causing the paper jam (check the users manual for supported paper media).
If you cannot find any problems with the paper, check the transport rollers for paper dust or other debris.
6. Paper Path
There are basically 6 different places within the machine where paper jams might occur. Paper tray: Possible causes: Paper Size / Orientation miss-match Burr on edge of paper tray. Gates holding the paper are too tight. Paper needs to be fanned. Paper tray unit not been properly installed Paper feed section: Paper jams when being fed out of paper tray. Multiple feeding of paper out of paper tray. Possible causes: Dirty or worn transport rollers. Duplex unit: Paper jams as it is being fed out of duplex unit. Paper jams as it is being fed into duplex unit. Possible causes: Junction gate solenoid broken Paper lodged in the paper path leading into duplex unit. Paper lodged in the paper path leading out of duplex unit. Transport rollers that drive paper into duplex unit may be dirty or worn. Fusing unit: Paper fed into pressure roller or heat roller resembles an accordion. Hairline strains of toner on copies. Toner lumps on copies . Paper jamming as it leaves copier. Possible causes: Dirty or worn pressure roller, heat roller, or fuser cleaning blade. Ricoh Europe B.V. Technical Training Centre www.get-u-wice.com 57
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6. Paper Path
Wrinkled paper Most likely to occur in the fusing unit. Moisture is the main cause for wrinkled paper.
6. Paper Path
Sorter: Copy jams as it enters the sorter. Possible causes: Sorter not plugged correctly into copier. Entrance ramp to sorter not aligned. Copier does not recognize sorter (sorter actuator switch fails to activate; possibly broken). Document feeder: Multiple originals being fed into document feeder. Originals not being fed out of document feeder. Copier does not recognize that there is a document feeder installed. Possible causes: Dirty or worn feed rollers. Dirty or worn separation rollers. Electrical problems (blown fuse in copier or in document feeder). Copier may need to be programmed to recognize document feeder.
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6. Paper / Original Jams
See SP mode or print a SMC data sheet to check Total Paper Jams Total Original Jams
6. Paper Path
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6. Paper Jams Locations
See SP mode or print a SMC data sheet to check Count number of jams for each location. Some sensors shows when the paper is to late or when the paper activate the sensor to long (lag)
» ON = paper late » OFF = paper lag
6. Paper Path
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6. Original Jam Detection
Show total jam count for each location.
6. Paper Path
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6. Plotter Jam History
See SP mode or print a SMC data sheet to check Overview for the last 10 paper jams.
» » » » Code (Paper Jam Location) Size (05 = A4 LEF) Counter Date
6. Paper Path
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6. Paper jams / misfeed
Check the paper Pre-punched
» Check if the machine supports pre-punched paper. » Check if the sensor is in the path of the punched hole. » Change paper direction LEF SEF
Paper size
» Try a different size
Does it jam only from one tray.
» Swap trays to eliminate the cause.
Paper jams from one paper tray. Check transfer settings. All trays have there own settings.
6. Paper Path
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7. Scanning
CCD (Charge Coupled Device) CIS (Contact Image Sensors) Cleaning is sufficient in most cases It is possible to change some filter settings, but rarely used because the expected effect is hardly noticeable and time consuming.
7. Scanning
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7. Frequent Feeding Jams
Check glass plate and feeder glass plate. Placing it upside-down can cause jams because one side of the exposure glass is coated.
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8. SP modes
SMC data Nvram reset SP mode In /output check Nvram backup (only GW machines) SMC data print Diagnostic page Maintenance SC Category A B C D See SM how to reset them
8. SP modes
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8. SP mode Examples
SMC data sheet is required to escalate a field problem.
8. SP modes
The SMC data sheet contains all settings of the machine. During the installation of the machine a SMC data sheet is printed an kept at the machine for later purposes. For example if the NVRAM must be replaced or reset, the machine settings are back to factory default. The SMC data sheet can be used to change these settings. SC History gives you an overview the latest 10 SC (Service Call) codes.
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9. Tips
9. Tips
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9. Tips
Copier reads that it is out of toner or constantly adds toner. Remove toner cartridge from copier and tap it on the inside of a waste paper basket. This releases any residual toner that might be stuck in the cartridge. Paper continues to jam in the copier, after you have removed all visible jams. Recently, copiers behave much like computers in that they both have temporary memory which holds all instructions and conditions while the unit is active. In order to clear this memory and possibly remove any false codes you must unplug the power cord.
9. Tips
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9. Tips
Document feeder jams intermittently with originals sticking to feed belt. Some document feeders require the contact glass be lubricated with silicon oil to prevent static electricity from building between the feed belt and the contact glass. Is the exposure glass mounted correctly. The copier you are servicing has a roll-up type sorter and you are getting intermittent paper jams at the entrance of the sorter. If the copier and sorter are on thick carpet, the copier may tend to sink into the carpet changing the level between the copier and sorter. Move the copier and the sorter to a hard surface, or, buy a plastic mat and roll the copier onto the mat. This also helps with dissipation of static electricity.
9. Tips
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9. Tips
Intermittent paper jams in paper tray unit. Check and see if either the feed rollers, or the separation rollers are worn or dirty. Clean roller or replace them. Check grounding. Cover open warnings In some cases sunlight can give some trouble. If sunlight hits a cover sensor the machine shows open cover. If you arrive at the site the sun has another position and therefore it is hard to find the cause. Power supply failure Check (blown fuse condition!!!, lose soldering point, burned components, broken wire, bad connections, etc.)
9. Tips
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9. Tips
Controller related SC Disconnect all accessories (like finisher, fax, etc.) Format Hard disk Check grounding Check power supply voltage Noise from the machine Use a screwdriver, place it on a part and listen where the noise is generated. Use only grease that is mentioned in the SM Do not use to much oil or grease.
9. Tips
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END
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