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The unit is factory adjusted to the optimum setting.  When the setting has been deviated or the parts have been
replaced, re-adjust the setting following the procedures described below.

As power source, use the stable AC power.

1

Connection
Connect AC cord of the display main unit.  (No connection to the AVC center unit)

2

Going into the process adjustment mode

[Procedure]

While pressing [BRIGHT] and [VOL DOWN] buttons simultaneously, switch on the main power.
Illumination of backlight indicates successful entry into this mode.  If backlight does not illuminate, press
[POWER] button of the remote controller.

[Contents]

Various adjustments can be performed manually by changing the value in the OSD shown on top left of the
screen.

Address Address data Data write

00

00

0

Write EEPROM setting

0

Display of test pattern inside of controller

00

00

0

Controller setting

0

Write controller setting

VOL UP

Move the cell rightward.  (For 1st and 3rd lines only.  Space is skipped.)  Toggle switch

VOL DOWN

Move the cell leftward.  (For 1st and 3rd lines only.  Space is skipped.)  Toggle switch

INPUT 

\

Decrease adjustment value.  (0 becomes F) ... 1st and 3rd lines  (1 becomes 0) ... 2nd
and 4th lines

INPUT 

|

Increase adjustment value.  (F becomes 0) ... 1st and 3rd lines  (0 becomes 1) ... 2nd
and 4th lines

BRIGHT

Move the lines.  Toggle switch

1st line(A) 

→

  2nd line(B) 

→

  3rd line(C) 

→

  4th line(D) 

→

  1st line(A) 

→

   ...

3

How to terminate special modes
Switch off the main power.

After parts replacement or repair, reset the lamp error (*1) in the following procedure.

Lamp error (*1)
When normal current does not run into the lamp because of inverter circuit failure or lamp damage, the display unit
microprocessor counts the occurrence of an error.  When error count reaches 5 times, the backlight illumination is
disabled for protection.  The error count can be reset by the following procedure.

After setting “0F 00 0” in the 1st line of the OSD, put 1 in the data write.  Upon this writing, the lamp error is reset
(with “0F 00 1”).
Switch off the main power once.
Switch on the power again and confirm that the backlight works again (to be illuminated).

The gradation test pattern held by inside LCD controller can be displayed.
It is useful to check the display function of the display unit.
Set “1” in the 2nd line of the OSD for display.

00

00

0
0

←

 Set this to 1 to display the test pattern.  Set 0 again to return.

00

00

0
0

Test pattern setting remains after switching off the power.  Make sure to set “0” again in the 2nd
line of the OSD to recover initial setting before terminating the process adjustment mode.
Then switch off the power.

(1) D/A converter

Address

Item

MIN

MAX

Initial setting

Remarks

10

BAL

00

FF

7F

Balance

11

VOL

00

FF

00

Volume

12

BASS

00

FF

7F

Bass

13

TREB

00

FF

7F

Treble

14

LOUD

00

FF

FF

Loudness

15

100HZ

00

FF

00

16

400HZ

00

FF

00

17

1KHZ

00

FF

00

18

4KHZ

00

FF

00

19

10KHZ

00

FF

00

1A

SVOL

00

FF

00

Sub volume

»

 Sound

Address

Item

MIN

MAX

Initial setting

Remarks

1C

V1H

00

FF

00

1D

V1L

00

FF

EA

1E

V34H

00

FF

85

1F

V34L

00

FF

CB

20

V41H

00

FF

87

21

V41L

00

FF

C3

22

V64H

00

FF

89

23

V64L

00

FF

AE

24

V128H

00

FF

8C

25

V128L

00

FF

82

26

V183H

00

FF

91

27

V183L

00

FF

72

28

V234H

00

FF

91

29

V234L

00

FF

59

2A

V247H

00

FF

94

2B

V247L

00

FF

47

2C

V255H

00

FF

94

2D

V255L

00

FF

42

2E

V256H

00

FF

94

2F

V256L

00

FF

3D

32

COMBIAS

00

FF

6A

33

M5VADJ

00

FF

AF

»

 Gradation

1st address 2nd address

item

MIN

MAX

Initial setting

Remarks

00

02

Initial setting

00

FF

4

00

06

Horizontal position

00

FF

00

00

07

Vertical position

00

FF

00

00

09

Delay adjustment

00

FF

00

00

10

Test pattern display

00

00

11

Test pattern selection

00

0F

00

00

F0

PWM control

00

0F

3

00

F3

PWM frequency

00

FF

0A

Lower

00

F4

PWM frequency

00

0F

05

Upper

00

F5

PWM duty

00

FF

E8

Lower

00

F6

PWM duty

00

0F

00

Upper

(2) Controller

Adjusting conditions

Adjusting method

+B adjustment (M+5VADJ item)

1. Hook up DC voltmeter at connector side of

FB2005.

Opposed bias adjustment (COM item)

1. Write “00 10 03” in the controller setting of

the OSD to produce solid black screen. 

*1

2. Apply the specified jig to the screen center.
3. Observe the output from the jig with

oscilloscope.

1. Adjust DC/DC5V line output voltage to 5.1 ±0.05Vp-p.

1. Adjust bias so that the waveform peak-to-peak is minimized.

*1: After adjustment, write “00 10 00” again in the setting to restore initial state.

Blue screen

Chec

k A

VC system oper

ation.

Whole screen in b

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k

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k A

VC system oper

ation.

Is there nor

mal output at pins 

(119), (120), (137), (138), (181) 

and (192) of IC4302?

Is there nor

mal output at pins (44), 

(46), (47) and (48) of IC4001?

Chec

k R4018, R4019, R4020 and 

R4021 and their per

ipher

al circuits

.

Chec

k IC4303 and its per

ipher

al 

circuits

.

Chec

k IC4001 and its per

ipher

al 

circuits

.

Is there nor

mal output at pin (113) 

of IC4302?

Chec

k IC4303 and its per

ipher

al 

circuits

.

Is there nor

mal output at pin (15) of 

P2001?

Chec

k Q2014 and its per

ipher

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circuits

.

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C

/DC po

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.

Is there nor

mal output at R39 

of AMP po

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r unit?

Is there nor

mal audio output at 

pins (1) and (3) of P1302?

Chec

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 AMP and po

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and per

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.

Is the v

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ltage 0V at R2041?

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 IC1304 and its 

per

ipher

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.

Is the v

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ltage 0V at 

R2038?

Chec

k IC2004 and its 

per

ipher

al circuits

.

Chec

k IC1308 and its 

per

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.

Replace BOSE speak

er

.