Panasonic Fax KX-FT21LA Schematic

ORDER NO. KM79905276C3

KX-FT21LA

PERSONAL FACSIMILEINTRODUCTION

KX-FT21LA

(for Latin America)

WARNING

This service information is designed for experienced repair technicians only and is not designed for use by the general public.

It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product. Products powered by electricity should be serviced or repaired only by experienced professional technicians.

Any attempt to service or repair the product or products dealt with in this service information by anyone else could result in serious injury or death.

C 1999 Kyushu Matsushita Electric Co., Ltd.

All rights reserved. Unauthorized copying and distribution is a violation of law.

- 1 -

KX-FT21LA

When you note the serial number, write down all 11 digits. The serial number may be found on the bottom of the unit.

TABLE OF CONTENTS
	Page
INTRODUCTION
Safety Precautions .............................................................................................................................	5
Insulation Resistance Test ..................................................................................................................	5
For Service Technicians......................................................................................................................	5
Battery Caution ..................................................................................................................................	6
AC Caution .........................................................................................................................................	6
Personal Safety Precautions...............................................................................................................	7
Specifications .....................................................................................................................................	8
Optional Accessories..........................................................................................................................	8
CCITT No.1 Test Chart ......................................................................................................................	9
Location of Controls ...................................................................................................................	10~11
Features ...........................................................................................................................................	12
Connections .....................................................................................................................................	13
Installation ..................................................................................................................................	14~16
Document stacker ............................................................................................................................	14
Document you can Send ..................................................................................................................	16
Maintenance Items and Component Locations ...........................................................................	17~20
TROUBLESHOOTING GUIDE
Troubleshooting Summary ................................................................................................................	22
User Recoverable Errors ..................................................................................................................	23
Document jam ..................................................................................................................................	24
Troubleshooting Details ..............................................................................................................	25~82
Programming and Lists...............................................................................................................	83~87
Test Functions ............................................................................................................................	88~89
Journal 3 ....................................................................................................................................	90~91
ADJUSTMENTS
Adjusting the Feeder Pressure .........................................................................................................	93
DISASSEMBLY INSTRUCTIONS
Diassembly Instructions ...........................................................................................................	95~105
How to Replace the Flat Package IC ......................................................................................	106~107

- 2 -

KX-FT21LA

CIRCUIT OPERATIONS
Connection Diagram .......................................................................................................................	109
General Block Diagram ..........................................................................................................	110~111
Control Section .......................................................................................................................	112~120
Facsimile Section ...................................................................................................................	120~132
MODEM Section ....................................................................................................................	133~140
NCU Section ..........................................................................................................................	141~142
ITS and Monitor Section .................................................................................................................	143
EXT. TEL.................................................................................................................................	144~145
Operation Panel......................................................................................................................	146~147
Power Supply Switching Board Section .................................................................................	148~151
PRINTED CIRCUIT BOARD (DIGITAL BOARD) .............................................................................	153~156
SCHEMATIC DIAGRAM (DIGITAL CIRCUIT) .........................................................................................	157
SCHEMATIC DIAGRAM (ANALOG CIRCUIT) ........................................................................................	158
PRINTED CIRCUIT BOARD (ANALOG BOARD) ............................................................................	159~160
PRINTED CIRCUIT BOARD (SWITCHING POWER SUPPLY) ..............................................................	161
SCHEMATIC DIAGRAM (SWITCHING POWER SUPPLY) ....................................................................	162
PRINTED CIRCUIT BOARD (OPERATION BOARD) .............................................................................	163
SCHEMATIC DIAGRAM (OPERATION CIRCUIT) ..................................................................................	164
TERMINAL GUIDE OF THE IC'S TRANSISTORS AND DIODES ...........................................................	165
FIXTURES AND TOOLS ........................................................................................................................	166
CABINET, MECHANICAL AND ELECTRICAL PARTS LOCATION ................................................	167~171
ACCESSORIES AND PACKING MATERIALS ........................................................................................	172
REPLACEMENT PARTS LIST ........................................................................................................	173~179

INTRODUCTION

- 3 -

KX-FT21LA

INTRODUCTION

	Page
Safety Precautions ...................................................................................	5
Insulation Resistance Test ........................................................................	5
For Service Technicians ...........................................................................	5
Battery Caution ........................................................................................	6
AC Caution ...............................................................................................	6
Personal Safety Precautions ....................................................................	7
Specifications ...........................................................................................	8
Optional Accessories ...............................................................................	8
CCITT No.1 Test Chart ............................................................................	9
Location of Controls .........................................................................	10~11
Features .................................................................................................	12
Connections ...........................................................................................	13
Installation ........................................................................................	14~16
Document stacker ..................................................................................	14
Documents you can send .......................................................................	16
Maintenance Items and Component Locations ................................	17~20

- 4 -

KX-FT21LA

		SAFETY PRECAUTIONS
			INTRODUCTION
	1.	Before servicing, unplug the AC power cord to prevent an electric shock.
	2.	When replacing parts, use only the manufacturer’s recommended components.
	3.	Check the condition of the power cord. Replace if wear or damage is evident.
	4.	After servicing, be sure to restore the lead dress, insulation barriers, insulation papers, shields, etc.
	5.	Before returning the serviced equipment to the customer, be sure to perform the following insulation resistance test to
		prevent the customer from being exposed to shock hazards.

INSULATION RESISTANCE TEST

1.Unplug the power cord and short the two prongs of the plug with a jumper wire.

2.Turn on the power switch.

3.Measure the resistance value with an ohmmeter between the jumpered AC plug and each exposed metal cabinet part (screwheads, control shafts, bottom frame, etc.).

Note: Some exposed parts may be isolated from the chassis by design. These will read infinity.

4.If the measurement is outside the specified limits, there is a possibility of a shock hazard. The equipment should be repaired and rechecked before it is returned to the customer.

Exposed metal part

Ohmmeter

Resistance = more than 1M (at DC 500 V)

FOR SERVICE TECHNICIANS

ICs and LSIs are vulnerable to static electricity.

When repairing, the following precautions will help prevent recurring malfunctions.

1)Cover the plastic part’s boxes with aluminum foil.

2)Ground the soldering irons.

3)Use a conductive mat on the worktable.

4)Do not touch the IC or LSI pins with bare fingers.

- 5 -

KX-FT21LA

BATTERY CAUTION

CAUTION

Danger of explosion if battery is incorrectly replaced.

Replace only with the same or equivalent type recommended by the manufacture. Dispose of used batteries according

to the manufacturer's instructions.

AC CAUTION

For safety, before closing the lower cabinet, please make sure of the following precautions.

1.The earth lead is fixed with the screw.

2.The AC connector is connected properly.

3.Wrap the AC lead around the core 2 times.

(BOTTOM VIEW)

	Earth Lead
3	(Ferrite Core) AC Inlet	AC Lead
	2		Earth Lead
			Earth
			Lead	Screw
			Washer	1

- 6 -

KX-FT21LA

PERSONAL SAFETY PRECAUTIONS

1. MOVING SECTIONS OF THE UNIT

Be careful not to let your hair, clothes, fingers, accessories, etc., become caught in any moving sections of the unit. The moving sections of the unit are the rollers and a gear. There is a separation roller and a document feed roller which are rotated by the document feed motor. A gear rotates the two rollers. Be careful not to touch them with your hands, especially when the unit is operating.

Sub roller

Rubber flap

Document feeder rollers

INTRODUCTION

Gear

White plate

Glass

2. LIVE ELECTRICAL SECTIONS

All the electrical sections of the unit supplied with AC power by the AC power cord are live. Never disassemble the unit for service with the AC power supply plugged in.

AC voltage is supplied to the primary side of the power supply unit.

Therefore, always unplug the AC power cord before disassembling for service.

Be careful of "High Voltage" in this area.

(Bottom view)

- 7 -

KX-FT21LA

	FEATURES
General	Integrated telephone system
Desktop type
LCD (Liquid Crystal Display) readout	Electric Volume Control
Help function	On-hook dialing
Copier function	Redialing function
	Temporary tone dialing
	Electric telephone directory
Facsimile
Space Saving Compact Design
Resolution: standard/fine/super fine/halftone
Copier Function
Automatic Document Feeder (10 Sheets)
Help Printout
Easy-to-view LCD (15 Characters)

- 8 -

		SPECIFICATIONS
Applicable Lines:	Public Switched Telephone Network
Document Size:	Max. 216 mm (81/2”) in width
Effective Scanning Width:	Max. 600 mm (235/8”) in length
	208mm (83/16”)
Recording Paper Size:	216 mm max. 30 m (81/2”• ~98’) roll
Effective Printing Width:	208 mm (83/16”)
Transmission Time*:	Approx. 15 s/page (Original mode)**
	Approx. 30 s/page (G3 Normal mode)
Scanning Density:	Horizontal:	8 pels/mm (203 pels/inch)
	Vertical:	3.85 lines/mm (98 lines/inch)—STANDARD mode
		7.7 lines/mm (196 lines/inch)—FINE/HALF TONE mode
		15.4 lines/mm (392 lines/inch)—SUPER FINE mode
Halftone Level:	64-level
Scanner Type:	Contact Image Sensor (CIS)
Printer Type:	Thermal Printing
Data Compression System:	Modified Huffman (MH), Modified READ (MR)
Modem Speed:	9,600 / 7,200 / 4,800 / 2,400 bps; Automatic Fallback
Operating Environment:	5ß C - 35ß C (41ß F - 95ß F), 45 % - 85 % RH (Relative Humidity)
Dimensions (H• ~W• ~D):	122 mm• ~338 mm• ~240 mm (413/16” • ~135/16”• ~97/16”)
Mass (Weight):	Approx. 2.5 kg (5.5 lb.)
Power Consumption:	Standby:	Approx. 5.5 W
	Transmission: Approx. 17 W
	Reception:	Approx. 30 W (When receiving the CCITT No. 1 Test Chart)
	Copy:	Approx. 30 W (When copying the CCITT No. 1 Test Chart)
	Maximum:	Approx. 120 W (When copying a 100 % black document)
Power Supply:	220 - 240 V AC, 50/60 Hz

*Transmission speed depends upon the contents of the pages, resolution, telephone line conditions and capability of the other party’s machine.

**The 15 second speed is based upon the CCITT No. 1 Test Chart.

Note:

Any details given in these instructions are subject to change without notice.

The pictures and illustrations in these instructions may vary slightly from the actual product.

KX-FT21LA

INTRODUCTION

OPTIONAL ACCESSORIES

Parts No.	Description	Comment
KX-A106	Standard thermal recording paper	216 mm • ~ 30 m (81/2"• ~98') roll,with 25 mm (1") core

- 9 -

KX-FT21LA

CCITT NO. 1 TEST CHART (Actual size)

- 10 -

1.OVERVIEW

LOCATION OF CONTROLS

Document entrance

Document stacker

Document guide(s)

Cover open button

Document exit

KX-FT21LA

INTRODUCTION

- 11 -

KX-FT21LA

2. CONTROL PANEL

			To change the receive
		To select a resolution	mode
			Display panel
			The arrow indicator on the
Dial keypad		Hookswitch	display points to your selected
			mode

		C		F
		B		E
		A		D
	I	L		O
	H
	G	K		N
		J	M
	S	V		Z
	R	U		Y
P	Q	T	W	X

TONE

TEL

FAX

FLASH

RESOLUTION

RECEIVE MODE

REDIAL/PAUSE

MONITOR

To change from pulse to tone	To dial without lifting the
during dialing	handset.

To redial the last number dialed

To insert a pause during dialing

To print a quick reference

For the Speed Dial

For the Telephone Directory with

Alpha-Search

For the One-Touch Dial

Command keys

	1	3
	4	6
	2	LOWER
	5

		VOLUME
HELP	DIRECTORY	SEARCH

To insert a hyphen

To keep the telephone number secret

To insert one character or one space

To select stations 4 6 for the One-Touch Dial

MENU

STOP

START/COPY/ SET

To stop an operation or cancel programming

To initiate or exit programming.

To adjust volumes

To select feature settings during programming.

To search for a stored name

To initiate fax transmission, reception or copying.

To store a setting during programming.

- 12 -

KX-FT21LA

CONNECTIONS

INTRODUCTION

Power cord
		Handset cord
To the power		Telephone
outlet (120V)
		line cord
	Connect to LINE .	To the single
		telephone line

Note:

When you operate this products, the power outlet should be near the product and easily accessible.

- 13 -

KX-FT21LA

INSTALLATION

3. INSTALLING THE RECORDING PAPER

1	Open the cover by pressing the cover open button
	and install the recording paper roll.

	correct	incorrect
	If the paper is secured with glue or tape, cut
	approximately 15 cm (6 inches) from the
2	beginning.	10 cm
	Pull the leading edge of the paper approximately
	10 cm (4 inches) out of the unit.
	Make sure that there is no slack in the
	paper roll.
3	Close the cover securely by pushing down on
	both ends.

4	Tear off the excess paper by pulling it
	towards you.

Note:

Only use the included roll of paper or specified recording paper, or else the print quality may be

affected and/or excessive thermal head wear may occur.

For accessory order information.

Cover open button

When the power cord is connected, everytime you close the cover a message will be printed. If the recording

paper is set to the wrong side, the message will not be printed. Install the paper correctly.

Document stacker

Install the document stacker.

Document stacker

- 14 -

4. SETTING YOUR LOGO

The logo can be your company, division or name.

1	Press		MENU .
			Display:	SYSTEM SET UP
				(PROG. SISTEMA)
2	Press	# , then 0		2 .
				YOUR LOGO
				(SU LOGO)
3	Press	START/COPY/SET .
				LOGO=
4	Enter your logo, up to 30 characters, by using
	the dial keypad. See the next page for details.
	Example: Bill
	1. Press		2 twice.
				LOGO=B
	2. Press		4 six times.			Cursor
				LOGO=Bi
	3. Press		5 six times.
				LOGO=Bil

4.Press to move the cursor to the next space and press 5 six times.

LOGO=Bill

KX-FT21LA

	/	INTRODUCTION
	1
2

MENU STOP

(Delete)

START/COPY/SET

To enter the same number key continuously, move the cursor to the next space.

5

6

Press START/COPY/SET .

SETUP ITEM	[	]
(NO. PROG.	[	])

Press MENU .

To correct a mistake			To insert a character
Press	or	to move the cursor to the incorrect	1. Press	or	to move the cursor to the
character, then make the correction.			position to the right of where you want to
To delete a character			insert the character.
			2. Press	2	(One-Touch Dial key 2) to insert a
Move the cursor to the character you want to delete and			space and enter the character.
press	STOP .

Note: Words in blankets ( ) are Spanish. A translated version for each market is available with this model series.

- 15 -

KX-FT21LA

To select characters with the dial keypad

Pressing the dial keys will select a character as shown below.

Keys

Characters

1

1

[

]

{

}

+

_

/

=

, .

_

,

?

: ;

2

A

B

C

a

b

c

2

3

D

E

F

d

e

f

3

4

G

H

I

g

h

i

4

5

J

K

L

j

k

l

5

6

M

N

O

m

n

o

6

7

P

Q

R

S

p

q

r

s

7

8

T

U

V

t

u

v

8

9

W

X

Y

Z

w

x

y

z

9

0

0

(

)

<

>

!

"

#

$

% &

\

@ ^

’

1 HYPHEN key (Used to insert a hyphen.)

2 INSERT key (Used to insert one character or one space.)

STOP	Delete key (Used to delete a character.)

key (Used to move the cursor to the left.)

key (Used to move the cursor to the right.)

To enter another character using the same number key, move the cursor to the next space.

Documents you can send
Minimum size		Maximum size		Effective scanning area
128mm	(5")	600mm	(23	Scanned
			") / 8	area
			5
128 mm				4 mm
(5")				208 mm (83/16")
		216 mm		Paper width
		(81/2")		216 mm (81/2")

Document weight

Single sheet:

45 g/m2 to 90 g/m2

(12 lb. to 24 lb.)

Multiple sheets (up to 10 sheets):

60 g/m2 to 75 g/m2

(16 lb. to 20 lb.)

Note:

Remove clips, staples or other similar fastening objects. Check that ink, paste or correction fluid has dried.

Do not send the following types of documents. Use copies for fax transmission. –Chemically treated paper such as carbon or carbonless duplicating paper –Electrostatically charged paper

–Heavily curled, creased or torn paper –Paper with a coated surface

–Paper with a faint image

–Paper with printing on the opposite side that can be seen through the front (e.g. newspaper)

-16 -

KX-FT21LA

MAINTENANCE ITEMS AND COMPONENT LOCATIONS

1. OUTLINE

MAINTENANCE AND REPAIRS ARE PERFORMED USING THE FOLLOWING STEPS.

1)Periodic maintenance

Inspect the equipment periodically and if necessary, clean any contaminated parts.

2)Check for breakdowns

Look for problems and consider how they arose.

If the equipment can be still used, perform copying, self testing or communication testing.

3)Check equipment

Perform copying, self testing and communication testing to determine if the problem originates from the transmitter, receiver or the telephone line.

4)Determine causes

Determine the causes of equipment problem by troubleshooting.

5)Equipment repairs

Repair or replace the defective parts and take appropriate measures at this stage to ensure that the problem will not recur.

6)Confirm normal operation of the equipment

After completing the repairs, conduct copying, self testing and communication testing to confirm that the equipment operates normally.

7)Record keeping

Make a record of the measures taken to rectify the problem for future reference.

INTRODUCTION

2. MAINTENANCE CHECK ITEMS/COMPONENT LOCATIONS

Document Sensor	Recording Paper
	Sensor
Read Position
Sensor	Platen Roller
Document Exit
Roller

Separation Roller

SWITCH 3

MOTOR

- 17 -

KX-FT21LA

2.1 MAINTENANCE LIST

NO.	OPERATION	CHECK	REMARKS
1	Document Path	Remove any foreign matter such as paper.
2	Rollers	If the roller is dirty, clean it with a damp cloth then dry thoroughly.	See page 19.
3	Thermal Head	If the thermal head is dirty, clean the printing surface with a cloth	See pages 20
		moistened with denatured alcohol (alcohol without water), then dry	and 104.
		thoroughly.
4	Glass	If the glass is dirty, clean the glass with a dry soft cloth.	See page 19.
5	Sensors	Document sensor (PS1), Read position sensor (PS2), Recording	See page 79.
		paper/cover open sensor (SW1).
6	Abnormal, wear and	Exchange the part.
	tear or loose parts	Check if the screws are tight on all parts.

2.2 MAINTENANCE CYCLE

		Cleaning		Replacement
No.	Item
		Cycle	Procedure	Cycle	Procedure
1	Separation Roller	3 months	See p. 19.	7 years	See p. 103.
	(Ref. No. 89)			(100,000 documents)
2	Separation Rubber	3 months	See p. 19.	7 years	See p. 98.
	(Ref. No. 85)			(100,000 documents)
3	Feed Rollers	3 months	See p. 19.	7 years	See p. 103.
	(Ref. No. 65)			(100,000 documents)
4	Thermal Head	3 months	See p. 20.	7 years	See p. 104.
	(Ref. No. 55)			(100,000 documents)

These values are only standard ones and may vary

depending on usage conditions.

- 18 -

KX-FT21LA

3. MAINTENANCE			INTRODUCTION
3.1 CLEANING THE DOCUMENT FEEDER UNIT
If misfeeding occurs frequently or if dirty patterns or black bands appear on a copied or transmitted document,
clean the document feeder.
1	Disconnect the power cord and the telephone	Telephone
	line cord.
2		line code
	Open the cover by pressing the cover open button.
3	Clean the document feeder rollers, sub roller and	Power cord
	rubber flap with a cloth moistened with isopropyl

rubbing alcohol, and let all parts dry thoroughly.

4	Clean the white plate and glass with a soft dry cloth.
5	Close the cover securely by pushing down on both
	ends.
6	Connect the power cord and the telephone line
	cord.

Caution:

Do not use paper products, such as paper towels or tissues, to clean the inside of the unit.

Separation roller

Cover	Sub roller

Document feeder rollers

Cover open button

- 19 -

KX-FT21LA

3.2 CLEANING THE THERMAL HEAD

If dirty patterns or black bands appear on a copied or received document, clean the thermal head.

1	Disconnect the power cord and the telephone
	line cord.

2	Open the cover by pressing the cover open button.
3	Clean the thermal head with a cloth moistened with
	isopropyl rubbing alcohol, and let it dry thoroughly.
4	ends.Close the cover securely by pushing down on both
5	cord.Connect the power cord and the telephone line

Caution:

To prevent a malfunction due to static electricity, do not use a dry cloth and do not touch the thermal head directly with your fingers.

Thermal head

Cover open button

Caution:

Do not push on the black cover

3.3 CLEANING THE PICK UP ROLLER

........Refer to page 103.

- 20 -

KX-FT21LA

TROUBLESHOOTING GUIDE

			Page
1.	Troubleshooting Summary ....................................................................		22
	1-1.	Troubleshooting .....................................................................	22
	1-2.	Precautions ...........................................................................	22
2.	User Recoverable Errors .......................................................................		23
3.	Troubleshooting Details ...................................................................		25~82
	3-1.	Outline ...................................................................................	25
	3-2.	Starting troubleshooting .........................................................	25
	3-3. Table of troubleshooting items ...............................................		26
	3-4.	Simple check list ....................................................................	27
	3-5.	ADF section .....................................................................	28~36
	3-6.	Communication section ...................................................	37~58
	3-7.	Digital board section ........................................................	59~70
	3-8.	Analog board section .......................................................	71~73
	3-9.	Power supply section ......................................................	74~77
	3-10. Operation board section ........................................................		78
	3-11. Sensor section ......................................................................		79
	3-12. Read section ...................................................................		80~81
	3-13. Thermal head section ............................................................		82
4.	Programming and Lists ...................................................................		83~87
5.	Test Functions ................................................................................		88~89
6.	Journal 3	........................................................................................	90~91

GUIDE TROUBLESHOOTING

- 21 -

KX-FT21LA

1. TROUBLESHOOTING SUMMARY

1-1. TROUBLESHOOTING

After confirming the problem by asking the user, troubleshoot according to the instructions and observe the following precautions.

1-2. PRECAUTIONS

1)If there is trouble with the print quality or the paper feed, first check if the installation space and the print

paper meets the specifications, the paper selection lever/paper thickness lever is set correctly, and the paper is set correctly without any slack.

2)Before troubleshooting, first check that the connectors and cables are connected correctly (not loose). If the problem occurs randomly, check it very carefully.

3)When connecting the AC power cord with the unit case and checking the operation, exercise utmost care when handling electric parts in order to avoid electric shock and short-circuits.

4)After troubleshooting, double check that you have not forgotten any connectors, left any loose screws, etc.

5)Always test to verify that the unit is working normally.

1.3 WHEN YOU DON'T KNOW HOW TO OPERATE THE UNIT, USE THE HELP FUNCTION

• How to use: 1. Press HELP .

2.Press or until the desired item is displayed.

3.Press START/COPY/SET .

- 22 -

KX-FT21LA

2. USER RECOVERABLE ERRORS

If the unit detects a problem, the following messages will appear on the display.

	Display Message		Cause & Remedy
			There is something wrong with the unit. Contact our service personnel.
	CALL SERVICE 1
			[This error is displayed when the thermal head dose not warm up. Check the
	(LLAME SERVICIO 1)
			thermistor on the thermal head and connector lead. (for technicians)]
	CALL SERVICE 2
	(LLAME SERVICIO 2)
			The cover is open. Close it.
	CHECK COVER
	(REVISAR LA TAPA)
			The document is not fed into the unit properly. Reinsert the document. If misfeeding
	CHECK DOCUMENT
			occurs frequently, clean the document feeder rollers and try again. If the problem
	(REVISAR DOC.)
			remains, adjust the feeder pressure.
			Attempted to transmit a document longer than 600 mm. Press the STOP button to
			remove the document. Divide the document into two or more sheets and try again.
			Memory (telephone numbers, parameters, etc.) has been erased. Re-program.
	CHECK MEMORY
			[The backup battery on the top of the digital board may be low or dead, so check it.]
	(REVISAR MEMORIA)
			The other party’s fax machine is busy or ran out of recording paper. Try again.
	NO RESPONSE
	(NO RESPUESTA)
	OUT OF PAPER		The unit runs out of recording paper. Install a recording paper.
	(SIN PAPEL)
			The other party’s fax machine does not have a polling feature. Check with the other
	POLLING ERROR
			party.
	(ERROR DE RECUP.)
	REDIAL TIME OUT		The other party’s fax machine is busy or ran out of recording paper. Try again.
	(CANCELA REDISC)
			The document is jammed. Remove the jammed document.
	REMOVE DOCUMENT
			[Alternately, turn off service code #559 to enable sending of documents longer than
	(REMOVER DOC.)
			600 mm.]
			A transmission error occurred. Try again.
	TRANSMIT ERROR
	(ERROR DE TRANS.)
	UNIT OVERHEATED		The unit is too hot. Let the unit cool down.
			[If many copies are nearly all black, this message will be displayed. When this occurs,
	(SOBRECALENTADO)
			open the front cover and let the unit cool down.]
			The explanations given in the [ ] are for serviceman only.
			Note:

GUIDE TROUBLESHOOTING

Use this USER RECOVERABLE ERRORS table when referring to LCD messages printed in this Service Manual.

Words in blankets ( ) are Spanish. A translated version for each market is available with this model series.

- 23 -

KX-FT21LA

Document jam

If the unit does not release the document during feeding, remove the jammed document as follows.

1 Open the cover by pressing the cover open button.

2 Remove the jammed document carefully.

Close the cover securely by pushing down

3 on both ends.

Note:

• Do not pull out the jammed paper forcibly.

before opening the cover.

Cover open button

- 24 -

KX-FT21LA

3. TROUBLESHOOTING DETAILS

3-1. OUTLINE

Troubleshooting guide provides a logical path of deduction to assist in locating a fault and suggests methods of restoring the unit to full working condition. Use the reported symptoms of the fault to determine the best troubleshooting method. Even difficult faults can be tracked to a specific block or area, for example, the "Digital Board" or "Image Sensor".

A variety of fault descriptions from customers often point to the same area and, for this reason, careful analysis of the reported symptoms is required. After every repair, test all functions to ensure no problems are evident.

3-2. STARTING TROUBLESHOOTING

Select the appropriate troubleshooting method according to the symptoms.

Power on.

Plug in the AC cord.

Check LCD.

LCD

slightly changes

or Blinking

LCD good

12:00AM

See the digital board section.

(See page 59.)

Yes

Already known symptom

AC

LCD

Blank

Blank LCD means that the power line is broken (open-circuit).

See the digital board section.

(See page 59.)

GUIDE TROUBLESHOOTING

No

Determine the symptom using		See the table for
the check list. (See page 25.)		troubleshooting items.

- 25 -

KX-FT21LA

3-3. TABLE OF TROUBLESHOOTING ITEMS

FUNCTION	SYMPTOM		SEE THIS PAGE.
	Skewed receiving image		34
Printing	Expanded print		34
	Image is distorted.		35
	Black or White vertical lines appear.		33
	No feed		28
ADF	Paper jam		29
(Auto Document Feeder)	Multiple feed		30
	Skew		31
Abnormal	Abnormal sound from the product		35
mechanical sound
Power supply	Voltage output is abnormal.		74
Operation panel	Keys are not accepted.		78
Sensor	If the electric circuit is the cause,		79
	"REMOVE DOCUMENT" will be displayed.
Communication	Cannot communicate by fax.		38
FAX, TEL	Error code is displayed.	}	38
(Analog/Digital board)	Cannot talk.		The analog board may cause these
	DTMF tone doesn't work.		symptoms.
	Handset/Monitor sound, volume		(Refer to page 72.)

- 26 -

KX-FT21LA

3-4. SIMPLE CHECK LIST

	FUNCTION		JUDGEMENT		REFERENCE
FAX operation		Transmission	OK • ^ NG
		Receiving	OK • ^ NG
Copy operation		FINE mode	OK • ^ NG
							TROUBLESHOOTING
		HALF TONE mode	OK • ^ NG
		Handset transceiver / receive	OK • ^ NG
Telephone operation		Monitor sound	OK • ^ NG
		Ringer sound	OK • ^ NG				GUIDE
		Dial operation	OK • ^ NG
		Volume operation	OK • ^ NG
Operation panel		Key check	OK • ^ NG		SERVICE CODE 561
		LCD check	OK • ^ NG		SERVICE CODE 558
Sensor		Sensor check	OK • ^ NG		SERVICE CODE 815
Clock			OK • ^ NG		Is the time kept correctly?
					Check with another clock.
External Telephone		Handset transceiver/receiver	OK • ^ NG
		Remote control	OK • ^ NG		Change to FAX receiving by pressing • – 9.
					(Refer to user mode #41 on page 57.)
				• ¦ Check according to the service code referring
					to the Test function on pages 88.

- 27 -

KX-FT21LA

3-5. ADF (Auto document feed) SECTION

(1) No document feed

When setting the document, confirm a beep tone.

NO

OK?

YES

When using thin paper etc., if the document will not feed. refer to the feed pressure adjustment (page 92).

Check the separation	OK		Check the sensor
spring for distortion.			lever movement.
				OK
			Check the sensor
			[Use the sensor check
			function (page 88)]
			and digital board.
			(pages 59 and 79)

NG Replace the sen- sor lever.

NG

Replace the defective parts.

Clean the separation roller.

OK?

OK

(page 103)

END

NG

Does the separation roller

NO Check the motor and

NG

OK?

Replace the motor

rotate? [Use the motor test

connector.

and connector.

function (page 88)]

YES

YES

Adjust the separation spring

NO

OK

Check the gear.

OK?

and clean or replace the pad.

END

NG

YES

NG

OK?

Replace the gear.

NO

OK

Replace the separation

OK?

YES

roller unit.

END

NG

YES

Replace the operating cover

unit.

NO

YES

To digital board

Is the phase signal from

Is the voltage at emitter

Check the power supply

section. (page 59)

pins 126-130 of IC4 out-

of Q7 +24 V?

unit section. (page 74)

put?

YES

NO

YES

Repair.

Is the solder at pins 126-

Is the voltage at collector

Replace IC8.

130 of IC4 OK?

of Q7 +24 V?

NO

YES

NO

OK?

Replace IC8.

Is the voltage at pin 11 of

YES

IC8 less than 2V?

NO

Replace the

YES

NO

END

motor.

Replace Q7.

OK?

YES

END

- 28 -

(2) Paper JAM

Open the lid and check			Check the paper jam for cause.
the feed route.
OK?		NO			Clean or replace the
					defective parts.
YES

KX-FT21LA

OK

OK? END

NG

Clean each roller. (page 103)

Check each sensor’s movement.

OK?

YES

Check each roller’s mount.

sensor lever works smoothly. [Use the sensor test function (page 88).]

TROUBLESHOOTING

OK?

OK

END

NG

Confirm if the tip of the read position

GUIDE

NO

OK

Repair or replace the

OK?

END

sensor lever.

NG

Check if the sensor

Go to the sensor section.

reacts while the flag is

(page 79)

moving.

Check if the separation, feed and pinch rollers are attached correctly.

OK?		NO		Repair the defective parts.		OK?	OK	END
						NG
YES

Check the white plate.

NG

Replace the white plate.

- 29 -

KX-FT21LA

(3)Multiple feed

When using thick paper, etc., if the document will not feed. refer to the feed pressure adjustment (page 92).

Confirm whether the pad is dirty or not and if it

Check the separation pad. is attached correctly.

		NO	Clean or replace the			OK
OK?			defective parts.		OK?		END
					NG
YES

Check if the separation					OK?			OK		END
spring is distorted.
					NG			OK
Clean each roller.					OK?					END
(page 103)
					NG

Replace the separation pad, roller and pressure spring.

- 30 -