Text preview for : ML-7000.RAR part of Samsung ML-7000 Samsung Printer ML7000 ML-7000.RAR
Back to : ML-7000.RAR | Home
ML-7000 Series
ML-7000P
ML-7000N
QwikLaser 7000
QwikLaser 7000P
QwikLaser 7000N
SERVICE Manual
Laser printer Contents
1. Precautions
2. Reference Information
3. Product Information
4. Disassembly
5. Trouble Shooting
6. Exploded Views & Parts List
7. Block Diagrams
8. PCB Diagrams
9. Port Thru
(Network Printer Card)
5. Troubleshooting
5-1 Print Quality
Error status Check Solution
1. Check HVPS output voltage 1. Refer to HVPS output spec
2. Check terminal contact for - Replace the engine board
Dark Image
HVPS. - Refer to "4 - 11"
2. Fix the terminal to contact well.
1. Check the toner quantity. 1. Replace image cartridge.
Light Image 2. Check HVPS output voltage 2. Refor to HVPS output spec.
3. Check the terminal contact for -Replace the engine board.
HVPS. 3. Fix the terminal to contact well.
1. Compare new image cartridge 1. Replace image cartridge
Horizontal Density with present one
Band. 2. Contamination of Transfer 2. Replace transfer roller
Roller
1. Contamination of Fuser Unit 1. Clean Fuser Unit or change
If not improved, replace it.
2. Contamination of Heat roller 2. Clean Heat Roller
- Refer to "4-5"
Print Contamination
3. Contamination of OPC Drum 3. Clean OPC Drum.
If not improved, replace image
cartridge.
1. Contamination of Fuser Unit 1. Clean Fuser Unit.
If not improved, replace it.
Toner on Backside - Refer to "4-5"
of printer page 2. Contamination of transfer Roller 2. Replace Transfer Roller
3. Contamination fo paper path 3. Remove the contamination on
paper path.
1. Check HVPS output voltage 1. Refer to HVPS output spec
2. OPC Drum contamination or - Replace the engine board
image cartridge life 2. Replace the image cartridge
3. Check the contamination of 3. Clean the lens with a soft
PTL lens dry cloth
Back Ground
4. Check the terminal contact for 4. Fix the terminal to contact well.
HVPS.
5. Check the contamination fo transfer 5. Relpace Transfer Roller
roller.
Vertical Black Streak 1. OPC Drum scar 1. Clean OPC Drum
and band 2. OPC Drum damage 2. Replace image cartridge
1. Contamination of LSU window 1. Clean LSU window
Vertical White Streak
2. If not improved,
replace image cartridge
1. OPC Drum scar or particle 1. Clean OPC Drum & roller
2. Heat roller scar or particle 2. Cleaning heat roller
3. Develope roller scar or particle 3. Clean the develope roller.
Partial Black Image If not improved,
(periodic) replace image cartridge.
4. Charge roller scar or particle 4. Clean the charge roller.
If not improved,
replace image cartridge.
Partial White Image 1. OPC Drum scar or particle 1. Clean OPC Drum
(not periodic) 2. Check the cartridge life 2. Replace image cartridge
Error status Check Solution
1. Check HVPS voltage 1. Refer to HVPS output spec.
- Replace the engine board
2. Check the GND OPC contact. 2. Fix contact points to fit well.
- Contact among GND OPC
contact points.
- Image cartridge.
- GND OPC terminal on frame
- GND OPC terminal on the
No image (all white) engine board
- Confirm the voltage between
GND-OPC and GND-Frame.
: -130V approx
3. Check LSU operation. 3. Replace the LSU.
- Refer to DCU control "05" -Refer to "4-8"
4. Compare new video board 4. Replace the video board.
with present one.
5. Toner empty 5. Replace the image cartridge.
1. Check the charger voltage 1. Refer to HVPS output spec
All Black Image 2. Check the terminal contact - Replace the engine board
3. Compare new video board with 2. Replace terminal
present one 3. Replace video board
5-2 HVPS Output Spec
DCU CODE NO. HVPS OUTPUT REMARK
CHARGER "01" - 1.55 KV 1. Turn off the printer
TRANSFER "-" "02" -1KV~ -1.4KV 2. Open the rear cover and disassemble
TRANSFER "+" "03" +1.8 KV the cover-shield.
BIAS "04" - 500 V 3. Connect the DCU on engine board and
SUPPLY "04" - 700 V close the rear cover.
OPC GND