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Lexmark X658DFE Service Manual - Page 292

Auto density sensing, Therefore

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7462 Auto density sensing The image density sensor assembly uses a reflection type sensor that detects a pre-placed toner patch and image on the photoconductor (drum) and outputs pulses when the central line of the patch image aligns with the central line of the detector. The sensor outputs pulses at the timing the patch image passes the sensor. Therefore, observing changes of intervals at which pulses are output leads to toner density detection. 3-66 Service Manual

Section	Page
Table of contents	3
Notices and safety information	15
Laser notice	15
Laser	15
Avis relatif à l’utilisation de laser	15
Avvertenze sui prodotti laser	15
Avisos sobre el láser	16
Declaração sobre Laser	16
Laserinformatie	16
Lasermeddelelse	16
Laserilmoitus	17
Huomautus laserlaitteesta	17
Laser-notis	17
Laser-melding	17
Avís sobre el Làser	18
Lithium warning	21
Consignes de sécurité	21
Norme di sicurezza	21
Sicherheitshinweise	22
Pautas de Seguridad	22
Informações de Segurança	22
Informació de Seguretat	23
Preface	24
1. General information	25
Maintenance approach	25
Printer overview	26
Printer configurations	26
Options	27
Supported paper sizes, types, and weights	28
Printer configurations	31
Tools required for service	32
Acronyms	33
2. Diagnostic information	35
Start	35
Confirm the installation status	36
Power-on Reset sequence	36
Entering Diagnostics Menu	36
User attendance messages	37
Error code table	45
Service checks	148
Sensor (input) service check	148
Sensor (fuser output) service check	148
Sensor (narrow media) service check	149
Sensor (duplex input) service check	149
Sensor (duplex input) service check (external duplex only)	150
Sensor (duplex exit) service check (external duplex only)	150
Sensor (pass through) service check	151
Sensor (envelope feeder empty) service check	151
Sensor (ADF top door interlock) service check	151
Switch (ADF closed interlock) jam service check	152
Sensor (ADF sheet through) static jam service check	153
Sensor (ADF sheet through) late jam service check 290.01	154
Sensor (ADF 1st scan) late jam service check	155
Sensor (ADF sheet through) lingering jam service check	157
Sensor (1st scan) static jam service check	159
Sensor (2nd scan) static jam service check	160
Sensor (2nd scan) lingering jam service check	160
Sensor (ADF media exit) late jam service check	162
ADF top door open jam service check	163
Media missing jam service check	164
Sensor (ADF media exit) static jam service check	165
Sensor (ADF media exit) late jam service check	166
Sensor (ADF media exit) lingering jam service check	168
Sensor (input) late jam service check.	170
Sensor (input) lingering jam service check.	172
Sensor (input) early jam service check	174
Sensor (input) static jam service check	175
Sensor (fuser output) late jam service check.	176
Sensor (fuser output) lingering jam service check.	177
Sensor (fuser output) static jam service check	179
Sensor (narrow media) late jam service check.	179
Sensor (narrow media) static jam service check	180
Sensor (duplex input) late jam service check.	181
Sensor (duplex input) lingering jam service check.	183
Sensor (duplex input) static jam service check.	184
Sensor (pass through) late jam service check	186
Sensor (pass through) lingering jam service check.	187
Sensor (pass through) static jam service check	188
Sensor (stapler pass through) late jam service check	189
Sensor (stapler pass through) lingering jam service check	190
Sensor (stapler pass through) static jam service check	190
Sensor (output pass through) late jam service check	191
Sensor (output pass through) lingering jam service check	191
Sensor (output pass through) static jam service check	192
Sensor (mailbox empty) late jam service check	192
Sensor (mailbox empty) lingering jam service check	193
Sensor (mailbox empty) static jam service check	194
Sensor (toner empty) service check	194
Sensor (scanner HP) service check	195
Sensor (ADF 2nd scan) late jam service check	195
NVRAM mismatch failure (950.00 through 950.29) service check	196
Image quality trouble	197
Printer Related Troubleshooting	197
Image Quality	198
ADF & Scanner Related Troubleshooting	217
ADF & Scanner Image Quality	218
Network service check	225
3. Diagnostic aids	227
Understanding the printer control panel	227
Understanding the home screen	228
Using the touch-screen buttons	230
Sample touch screen	230
Other touch-screen buttons	231
Accessing service menus	233
Diagnostics Menu	234
Entering Diagnostics Menu	234
Available tests	234
Registration (printer)	237
PRINT TESTS	238
HARDWARE TESTS	240
DUPLEX TESTS	242
INPUT TRAY TESTS	245
OUTPUT BIN TESTS	246
BASE SENSOR TEST	246
DEVICE TESTS	247
PRINTER SETUP	248
EP SETUP	250
REPORTS	251
EVENT LOG	251
SCANNER TESTS	253
Configuration menu (CONFIG MENU)	254
Entering Configuration Menu	254
Available menus	254
Maintenance Counter Value	255
Reset Maintenance Counter	255
USB Scan to Local	256
Print Quality Pages	256
Reports	257
SIZE SENSING	257
Panel Menus	258
PPDS Emulation	258
Factory Defaults	259
Energy Conserve	259
Min Copy Memory	260
NumPad Job Assist	260
Format Fax Storage	260
Fax Storage Location	260
ADF Edge Erase	260
FB Edge Erase	261
Scanner Manual Registration	261
Disable Scanner	262
Paper Prompts	262
Envelope Prompts	262
Action for Prompts	263
Jobs On Disk	264
Disk Encryption	264
Wipe Disk	265
Font Sharpening	265
Require Standby	265
LES Applications	266
Key Repeat Initial Delay	266
Key Repeat Rate	266
Wiper Message	266
Clear Custom Status	266
Exit Configuration Menu	267
Printer configurations	268
Printer theory	269
Models X651, X652, X654 and X656 paper path rolls and sensors	269
Model X658 paper path rolls and sensors	270
Functions of main components	270
Media tray assembly	272
Multi-purpose feeder (MPF)	274
Supported paper sizes, types, and weights	275
Registration	277
Transfer	278
Polygon printhead assembly	279
Fuser	280
Fuser components	281
Exit	283
Drive	283
Electrical components and controller	284
Control	286
Printhead control	286
Fuser control	286
Xerographic and print cartridge components	287
Document scanning at ADF	293
Document scanning at platen	293
Names and functions of components	293
Scanner unit assembly	293
Names and functions of components	296
ADF	296
High Capacity Input Tray (HCIT) tray assembly	299
250-sheet/550-sheet tray assembly	300
The following is a cross section of the printer and the tandem tray module, showing the main components directly associated with the media path and transport.	303
Models X651, X652, X654 and X656 paper path rolls and sensors	303
Model X658 paper path rolls and sensors	304
Media tray assembly	305
Duplex	307
Paper jams	308
Understanding jam numbers and locations	308
Adjusting skew	318
Flatbed scanner skew adjustment	319
ADF skew adjustment (via ADF document tray)	319
ADF skew adjustment (Via duplex CCD assembly)	321
4. Repair information	323
Handling ESD-sensitive parts	323
Adjustments	324
Polygon printhead mechanical registration adjustment	324
Alignment assembly adjustment	324
Fuser solenoid adjustment	326
Gap adjustment	326
Removal procedures	327
Before starting service work	327
Charge roll assembly removal (X651, X652, X654, X656, and X658)	328
Duplex assembly removal (X654, X656, and X658)	329
Duplex cooling fan removal (X654, X656, and X658)	330
Duplex drive motor assembly removal (X654, X656, and X658)	331
Duplex input sensor assembly removal (X654, X656, and X658)	332
Duplex guide assembly, front removal (X654, X656, and X658)	332
Media turn guide removal (X651, X652, X654, X656, and X658)	334
Fuser access door assembly removal (X651, X652, X654, X656, and X658)	334
Main cooling fan removal (X651, X652, X654, X656, and X658)	335
Fuser drive release linkage removal (X651, X652, X654, X656, and X658)	337
Fuser unit assembly removal (X651, X652, X654, X656, and X658)	337
Fuser wiper cover assembly removal (X651, X652, X654, X656, and X658)	338
HVPS card assembly removal (X651, X652, X654, X656, and X658)	339
Inner deflector removal (X651, X652, X654, X656, and X658)	339
Option drive shaft removal (X651, X652, X654, X656, and X658)	340
Main drive motor assembly removal (X651, X652, X654, X656, and X658)	342
Alignment assembly removal (X651, X652, X654, X656, and X658)	343
Media out actuator removal (X651, X652, X654, X656, and X658)	345
Media support removal (X651, X652, X654, X656, and X658)	345
Tray roller catch assembly removal (X651, X652, X654, X656, and X658)	346
MPF cam gear removal (X651, X652, X654, X656, and X658)	346
MPF lift plate assembly removal (X651, X652, X654, X656, and X658)	347
MPF media out actuator removal (X651, X652, X654, X656, and X658)	347
MPF pick roll assembly removal (X651, X652, X654, X656, and X658)	348
MPF pick solenoid assembly removal (X651, X652, X654, X656, and X658)	348
Pick arm assembly removal (X651, X652, X654, X656, and X658)	351
Pick roll assembly removal (X651, X652, X654, X656, and X658)	353
Print cartridge cooling fan removal (X651, X652, X654, X656, and X658)	353
Print cartridge clamp assembly removal (X651, X652, X654, X656, and X658)	354
Print cartridge ID connector assembly removal (X651, X652, X654, X656, and X658)	355
Printhead assembly removal (X654, X656, and X658)	356
Connection access cover, rear removal (X651, X652, X654, X656, and X658)	357
Connection bezel assembly, rear removal (X651 and X652)	358
Door assembly, rear removal (X651, X652, X654, X656, and X658)	359
Duplex guide assembly, rear removal (X654, X656, and X658)	359
Cover assembly, rear lower (X654, X656, and X658)	361
Redrive motor assembly removal (X654, X656, and X658)	361
Sensor (duplex input) removal (X654, X656, and X658)	364
Sensor (media low) removal (X651, X652, X654, X656, and X658)	364
Sensor (media empty) removal (X651, X652, X654, X656, and X658)	364
Sensor (toner empty) removal (X651, X652, X654, X656, and X658)	365
Sensor (input) removal (X651, X652, X654, X656, and X658)	365
Sensor shield assembly removal (X651, X652, X654, X656, and X658)	366
Standard bin actuator assembly removal (X651, X652, X654, X656, and X658)	367
Sensor (standard bin exit) actuator removal (X651, X652, X654, X656, and X658)	367
Sensor (toner density) removal (X651, X652, X654, X656, and X658)	368
Switch (media size) assembly removal (X651, X652, X654, X656, and X658)	368
LVPS card assembly removal (X654, X656, and X658)	370
Access door removal (X651, X652, X654, X656, and X658)	371
System card assembly removal (X651, X652, X654, X656, and X658)	373
Transfer roll assembly removal (X651, X652, X654, X656, and X658)	376
Transfer roll bracket assembly, left removal (X651, X652, X654, X656, and X658)	377
Transfer roll bracket assembly, right removal (X651, X652, X654, X656, and X658)	377
Transfer deflector removal (X651, X652, X654, X656, and X658)	379
Redrive assembly removal (X651, X652, X654, X656, and X658)	380
ADF feed / pick roll assembly removal (models X651, X652, X654, X656, and X658)	381
ADF separator roll removal	381
ADF separator torque limiter assembly removal (models X651, X652, X654, X656, and X658)	383
ADF cover, front removal (models X651, X652, X654, X656, and X658)	384
ADF cover, rear removal (models X651, X652, X654, X656, and X658)	385
ADF document tray assembly removal (models X651, X652, X654, X656, and X658)	385
ADF top door assembly removal (models X651, X652, X654, X656, and X658)	386
ADF controller card removal (models X651, X652, X654, X656, and X658)	387
ADF platen cushion removal (models X651, X652, X654, X656, and X658)	388
ADF lower door assembly removal (models X651, X652, X654, X656, and X658)	388
ADF duplex CCD scan glass assembly removal (models X654, X656, and X658)	389
ADF duplex CCD assembly removal (models X654, X656, and X658)	390
ADF pinch roll assembly removal (models X651, X652, X654, X656, and X658)	392
ADF turn guide removal (models X651, X652, X654, X656, and X658)	393
ADF media pinch pad assembly removal (models X651, X652, X654, X656, and X658)	394
Sensor (ADF media exit) fan bracket assembly removal (models X654, X656, and X658)	395
ADF transport drive motor bracket assembly w/cable removal (models X651, X652, X654, X656, & X658)	396
ADF feed drive motor assembly removal (models X651, X652, X654, X656, and X658)	396
ADF pick roll position cam assembly removal (models X651, X652, X654, X656, and X658)	398
ADF solenoid assembly removal (models X651, X652, X654, X656, and X658)	399
Sensor (ADF top door interlock) removal (models X651, X652, X654, X656, and X658)	399
Sensor (ADF lower door interlock) removal (models X651, X652, X654, X656, and X658)	400
Sensor (ADF 2nd scan) removal (models X651, X652, X654, X656, and X658)	400
Sensor (ADF 1st scan) removal (models X651, X652, X654, X656, and X658)	401
Sensor (ADF sheet through) removal (models X651, X652, X654, X656, and X658)	402
Sensor (ADF document set) removal (models X651, X652, X654, X656, and X658)	403
Switch (ADF closed interlock) removal (models X651, X652, X654, X656, and X658)	404
ADF unit assembly removal (models X651, X652, X654 and X656)	405
ADF unit assembly removal (model X658)	405
ADF left hinge removal (models X651, X652, X654, X656, and X658)	406
ADF right hinge removal (models X651, X652, X654, X656, and X658).	407
Cover, left rear corner removal (model X658)	408
Cover, right rear corner removal (model X658)	408
Sensor (ADF media exit) fan bracket assembly removal (models X652, X654, X656, and X658)	409
Sensor (ADF media exit) bracket assembly removal (X651)	410
Scanner CCD assembly removal (models X651, X652, X654, X656, and X658)	411
Scanner reference LED cable assembly removal (models X651, X652, X654, X656, and X658)	412
Scanner unit assembly removal (models X651, X652, X654 and X656)	412
Scanner unit assembly removal (model X658)	414
MPF tray door assembly removal (models X651, X652, X654, and X656)	415
MPF tray door assembly removal (model X658)	417
Fuser access assembly removal (models X651, X652, X654, X656, and X658)	419
Output cover assembly removal (model X651, X652, X654 and X656)	419
Output cover assembly removal (model X658)	420
Redrive assembly removal (model X658)	420
Redrive assembly removal (models X651, X652, X654, and X656)	421
Laser cover removal (model X658)	422
Laser cover removal (models X651, X652, X654, and X656)	424
Standard output bin LED assembly removal (models X651, X652, X654, and X656)	426
MPF media guide assembly removal (model X658)	427
Operator panel assembly removal (model X658)	428
Operator panel door assembly removal (models X651, X652, X654, and X656)	430
Operator panel cover latch assembly removal (models X651, X652, X654, and X656)	433
Print cartridge cover assembly removal (model X658)	434
Side cover, right removal (model X658)	435
Side cover, right removal (models X651, X652, X654, and X656)	436
Side cover, left removal (model X658)	436
Side cover, left removal (models X651, X652, X654, and X656)	437
Door assembly, rear removal (models X651, X652, X654, X656, and X658)	438
Cover, rear lower removal (models X651, X652, X654, X656, and X658)	439
Scanner support cover, right rear removal (model X658)	441
Scanner support inner cover, right removal (model X658)	442
Scanner support cover, right removal (model X658)	443
Scanner controller card assembly removal (model X658)	443
Scanner controller card assembly removal (models X651, X652, X654 and X656)	446
Scanner cover, rear removal (models X651, X652, X654, X656, and X658)	447
Scanner cover, left removal (models X651, X652, X654 and X656)	448
Scanner cover, left removal (model X658)	449
Scanner cover, right removal (models X651, X652, X654, and X656)	450
Scanner cover, right removal (model X658)	450
Scanner cover, front removal (models X651, X652, X654 and X656)	451
Scanner cover, front removal (model X658)	452
Scanner platen glass cover assembly removal (model X658)	453
Scanner platen glass cover assembly removal (models X651, X652, X654 and X656)	454
Scanner support platform removal (models X651, X652, X654, and X656)	455
Carriage belt tensioner assembly removal (models X651, X652, X654, X656, and X658)	457
Carriage drive motor assembly with cable removal (models X651, X652, X654, X656 & X658)	458
Carriage belt removal (models X651, X652, X654, X656, and X658)	459
Scanner / ADF duplex CCD exposure lamp removal (models X651, X652, X654, X656, and X658)	461
Scanner interface card assembly removal (models X651, X652, X654, X656, and X658)	462
Scanner cooling fan filter removal (models X651, X652, X654, X656, and X658)	463
Scanner cooling fan removal (models X651, X652, X654, X656, and X658)	463
Scanner support cover, left rear removal (model X658)	464
Scanner support cover, left front removal (model X658)	465
Scanner support cover, left removal (model X658)	466
Scanner support inner cover, left removal (model X658)	466
Sensor (platen glass length) assembly removal (models X651, X652, X654, X656, and X658)	467
Sensor (scanner HP) assembly w/bracket removal (models X651, X652, X654, X656 & X658)	468
LVPS cooling fan	468
Option removals	470
High capacity input tray	470
High capacity input tray (HCIT) media tray assembly removal	471
High capacity input tray (HCIT) tray cover, front removal	472
High capacity input tray (HCIT) cover, rear removal	474
High capacity input tray (HCIT) cover, right removal	476
High capacity input tray (HCIT) cover, left removal	478
High capacity input tray (HCIT) anti-tip latch assembly removal	479
High capacity input tray (HCIT) drawer slide assembly removal	481
High capacity input tray (HCIT) tray lift drive motor assembly removal	481
High capacity input tray (HCIT) controller card assembly removal	483
High capacity input tray (HCIT) media size actuator assembly removal	484
Sensor (HCIT tray raised HP) with cable assembly removal	486
Sensor (HCIT pass through) with cable removal	487
High capacity input tray (HCIT) pick arm bracket assembly removal	489
High capacity input tray (HCIT) tray closed latch with spring removal	491
250-sheet media tray assembly removal	492
250-sheet option drawer assembly removal	492
250-sheet pick arm bracket assembly removal	493
250-sheet media out actuator removal	494
Anti-tip latch assembly removal	494
250-sheet frame assembly removal.	495
Sensor (pass through) with cable removal	495
250-sheet controller card assembly removal	498
Media size actuator removal	500
Media tray catch spring removal	501
Tray roller catch assembly removal	502
550-sheet option tray assembly	504
550-sheet media tray assembly removal	505
550-sheet option drawer assembly removal	505
550-sheet pick arm bracket assembly removal	506
550-sheet bellcrank recoil spring removal	507
Media out actuator removal (models T652 and T654)	507
Anti-tip latch assembly removal	508
550-sheet frame assembly removal	509
Upper interface cable assembly removal	511
Lower interface cable assembly removal	511
Sensor (pass through) with cable removal	512
550-sheet controller card assembly removal	512
Media size actuator removal	514
550-sheet option drive shaft with spring removal	515
Media tray catch spring removal	516
Media tray roller catch assembly removal	516
Stapler finisher rear door assembly removal	517
Stapler finisher right cover removal	517
Stapler finisher left cover removal	517
Stapler finisher top cover removal	517
Stapler finisher handle cover removal	517
Stapler finisher ADF output bin removal	517
Stapler finisher LED sensor cover removal	517
Stapler finisher sensor (finisher media bin present) removal	517
Stapler finisher standard output bin LED and LED clear lens removal	518
Stapler finisher tamper recoil spring removal	518
Stapler finisher tamper drive belt removal	518
Stapler finisher tamper drive motor assembly removal	518
Stapler finisher media stack flap and media stack flap actuator removal	518
Stapler finisher stapler unit assembly removal	518
Stapler finisher bin spring removal	518
Stapler finisher controller card assembly removal	519
Stapler finisher paddle drive motor assembly removal	519
Stapler finisher sensor (media stack) removal	519
Stapler finisher sensor (paddle HP) removal	519
Stapler finisher sensor (stapler access door interlock) removal	519
Stapler finisher sensor (tamper HP left and right) removal	519
Stapler finisher sensor (bin full send) removal	519
Stapler finisher sensor (bin full receive) removal	519
Stapler finisher sensor (media in stapler) removal	520
Stapler finisher stapler cover removal	520
Stapler finisher sensor (diverter HP) removal	520
4-bin mailbox assembly left cover removal	520
4-bin mailbox assembly controller card assembly removal	520
4-bin mailbox assembly sensor (media bin full) removal	520
4-bin mailbox assembly sensor (diverter gate HP) removal	520
4-bin mailbox assembly rear door assembly removal	521
4-bin mailbox assembly left rear inner cover removal	521
4-bin mailbox assembly right cover removal	521
4-bin mailbox assembly right rear inner cover removal	521
4-bin mailbox assembly LED card assembly removal	521
4-bin mailbox assembly media output bin light pipe removal	521
4-bin mailbox assembly top cover removal	521
4-bin mailbox assembly diverter gate solenoid removal	521
4-bin mailbox assembly transport solenoid removal	522
4-bin mailbox assembly media diverter spring removal	522
4-bin mailbox assembly media bin diverter (bin 1 through 3) removal	522
4-bin mailbox assembly media bin diverter (bin 4) removal	522
4-bin mailbox assembly sensor (pass through) removal	522
4-bin mailbox assembly sensor (mailbox empty) removal	522
4-bin mailbox assembly standard output bin LED removal	523
4-bin mailbox assembly LED clear lens removal	523
4-bin mailbox assembly media bin full actuator removal	523
Offset stacker rear door assembly removal	523
Offset stacker right cover removal	523
Offset stacker left cover removal	523
Offset stacker top cover removal	523
Offset stacker handle cover removal	523
Offset stacker ADF output bin removal	524
Offset stacker LED sensor cover removal	524
Offset stacker sensor (finisher media bin present) removal	524
Offset stacker standard output bin LED and LED clear lens removal	524
Offset stacker tamper recoil spring removal	524
Offset stacker tamper drive belt removal	524
Offset stacker tamper drive motor assembly removal	524
Offset stacker media stack flap and media stack flap actuator removal	525
Offset stacker bin spring removal	525
Offset stacker controller card assembly removal	526
Offset stacker paddle drive motor assembly removal	526
Offset stacker sensor (media stack) removal	526
Offset stacker sensor (paddle HP) removal	526
Offset stacker sensor (tamper HP left and right) removal	526
Offset stacker sensor (bin full send) removal	526
Offset stacker sensor (bin full receive) removal	526
Offset stacker sensor (diverter HP) removal	526
5. Connector locations	529
Locations	529
Sensors-ADF	529
Sensors-Flatbed	529
6. Preventive maintenance	531
Safety inspection guide	531
Lubrication specifications	531
Scheduled maintenance	531
Maintenance kit	531
Maintaining the printer	532
Cleaning the exterior of the printer	532
Cleaning the scanner glass	532
7. Parts catalog	535
How to use this parts catalog	535
Assembly 1: Covers (X651, X652, X654, and X656)	536
Assembly 2: Covers 1 (X658)	538
Assembly 3: Covers 2 (X658)	540
Assembly 4: Media path, pick arm and ducts	542
Assembly 5: Drive motor assemblies	544
Assembly 6: Printhead, fuser assembly, and electronics	546
Assembly 7: Flatbed scanner	548
Assembly 8: ADF covers	550
Assembly 9: ADF feed and drive	552
Assembly 10: ADF electronics	554
Assembly 11: 550 Sheet option tray assembly (X658)	556
Assembly 12: 250 Sheet option tray assembly (X651, X652, X654, and X656)	558
Assembly 13: 550 Sheet option tray assembly (X651, X652, X654, and X656)	560
Assembly 14: HCIT Sheet option tray assembly (X651, X652, X654, and X656)	562
Assembly 15: Finisher assembly #1	564
Assembly 16: Finisher assembly #2	566
Assembly 17: Offset stacker	568
Assembly 18: 4-bin mailbox assembly #1	570
Assembly 19: 4-bin mailbox assembly #2	572
Assembly 20: 4-bin mailbox assembly #3	574
Assembly 21: Envelope feeder	576
Assembly 22: Electrical cables	578
Assembly 23: Miscellaneous	580
Assembly 24: Miscellaneous (continued)	581
Index	582

Match case Limit results 1 per page

3-66

Service Manual

7462

Auto density sensing

The image density sensor assembly uses a reflection type sensor that detects a pre-placed toner patch and

image on the photoconductor (drum) and outputs pulses when the central line of the patch image aligns with

the central line of the detector. The sensor outputs pulses at the timing the patch image passes the sensor.

Therefore, observing changes of intervals at which pulses are output leads to toner density detection.