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COLD  RESET
The cold reset clears all data including preset data stored in the 
RAM to initial conditions. Execute this mode when returning the 
set to the customer.
Procedure:
1.  Press three buttons of [

x

/CANCEL], [VOL +] and [

?

/

1

] si-

multaneously.

2.  The system is reset and becomes standby states.

COMMON  TEST  MODE
This mode is used to check operations of amplifi er.
Procedure
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press three buttons of [TUNER/BAND], [

x

/CANCEL] and 

[ENTER] simultaneously.

3.  When the COMMON test mode is activated, “AUDIO IN” is 

displayed on the liquid crystal display and “cPLAY SLEEP” 
blink on the fl uorescent indicator tube.

4.  Each time [EQ] button on the remote commander is pressed, 

the display changes starting “TONE MAX”, “TONE MIN” 
and “TONE FLAT” this order.

5.  Press the [VOL –] button, “VOLUME MIN” is displayed 

on the fl uorescent indicator tube. Press the [VOL +] button, 
“VOLUME MAX” is displayed on the fl uorescent indicator 
tube.

6.  To release this mode, press the [

?

/

1

] button.

PANEL  TEST  MODE
This mode is used to check the liquid crystal display, LED, model, 
destination, software version and key.
Procedure
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press three buttons of [TUNER/BAND], [DSGX] and [EN-

TER] simultaneously.

3.  All segments on the fl uorescent indicator tube, [STANDBY] 

LED and [BLUETOOTH OPR] LED (BX50BTi only) light 
up.

4.  Press the [ENTER] button, the model and destination are alter-

nately displayed on the fl uorescent indicator tube.

5.  Press the [ENTER] button again, MC version is displayed on 

the fl uorescent indicator tube.

6.  Each time [ENTER] button is pressed, the display changes 

starting from MC version, GC version, BT version (BX50BTi 
only), CLA version, CD version, CDD version, CDMA ver-
sion, CDMB version, BDA version, BDB version, ST version, 
TA version and TM version this order, and returns to the MC 
version display.

7. When [

x

/CANCEL] button is pressed while the MC version 

is displayed, year, month and day of the software creation is 
displayed. When [

x

/CANCEL] button is pressed again, the 

display returns to the MC version display.

8.  Press the [DSGX] button, the key test mode is activated and 

“K 0” is displayed on the fl uorescent indicator tube.

9.  Each time a button is pressed, “K” value increases. However, 

once a button is pressed, it is no longer taken into account.

 

All keys are pressed, display becomes “K19” (BX20i)/“K20” 
(BX50BTi).

10. Press the [VOL +] button, the key AD monitor mode is acti-

vated and “FFFFFF” is displayed on the fl uorescent indicator 
tube.

11. Each time a button is pressed, the AD of each button is dis-

played on the fl uorescent indicator tube.

12.  To release this mode, press three buttons in the same manner as 

step 2, or disconnect the power cord.

TUNER  STEP  CHANGE
(Except BX20i: AEP model)
A step of AM tuning interval can be changed over between 9 kHz 
or 10 kHz.
Procedure
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press the [TUNER/BAND] button to select “AM” .
3.  Press the [

?

/

1

] button again to turn the power off.

4.  Press two buttons of [ENTER] and [

?

/

1

] simultaneously.

5.  The message “STEP 9” or “STEP 10” is displayed on the fl uo-

rescent indicator tube and thus the tuning interval is changed 
over.

CD  SHIP  MODE
This mode moves the optical pick-up to the position durable to 
vibration. Use this mode when returning the set to the customer 
after repair.
Procedure
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press the [FUNCTION] button to select “CD”.
3.  Press three buttons of [DSGX], [VOL +] and [

A

] simultane-

ously.

4.  After the “STANDBY” display blinks, “LOCK” is displayed 

on the fl uorescent indicator tube, the ship mode is set.

CD  SHIP  MODE  &  MEMORY  CLEAR
This mode is used to perform CD ship mode and cold reset simul-
taneously.
Procedure
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press three buttons of [

x

/CANCEL], [VOL +] and [

A

] simul-

taneously.

3.  After the “STANDBY” display blinks, “LOCK” is displayed 

on the fl uorescent indicator tube the ship mode is set and the 
system is reset.

ANTITHEFT  LOCK  MODE
This mode is used to unable to take sample disc out of disc tray in 
the shop.
Procedure
1.  Press the [

?

/

1

] button to turn the set on.

2.  Press the [

A

] button to open the disc tray and set the CD disc.

3.  Press the [

A

] button to close the disc tray.

4.  Press the [FUNCTION] button to select “CD”.
5.  Press two buttons of [

x

/CANCEL] and [

A

] for 5 seconds.

6.  The message “LOCKED” is displayed on the fl uorescent indi-

cator tube and the disc tray is locked. (Even if pressing the Z 
button, the message “LOCKED” is displayed on the fl uores-
cent indicator tube and the disc tray is locked)

7.  To release from this mode, press two buttons of [

x

/CANCEL] 

and [

A

] for 5 seconds.

8.  The message “UNLOCKED” is displayed on the fl uorescent 

indicator tube and the disc tray is unlocked.

CD  POWER  MANAGE
This mode is used to changed over CD power on/off for decreasing 
of reception noise in the tuner mode.
Procedure
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press the [FUNCTION] button to select “CD”.
3.  Press the [

?

/

1

] button again to turn the power off.

4.  Press two buttons of [

x

/CANCEL] and [

?

/

1

] simultaneously.

5.  The message “CD POWER”, “ON” or “CD POWER”, “OFF” 

is displayed on the fl uorescent indicator tube, and CD power 
on/off is changed over in the tuner mode.

CD  SERVICE  MODE
This mode can run the CD sled motor freely. Use this mode, for 
instance, when cleaning the optical pick-up.
Procedure:
1.  Press the [

?

/

1

] button to turn the power on.

2.  Press the [FUNCTION] button to select “CD”.
3.  Press three buttons of [

x

/CANCEL], [VOL –] and [

A

] simul-

taneously, the message “SERVICE MO” is displayed on the 
fl uorescent indicator tube.

4.  Press the [

l

 

m

 TUNE –] button to move the optical pick-

up to inside track and the message “SLED IN” is displayed on 
the  fl uorescent indicator tube, or press the [

M

 

L

 TUNE 

+] button to outside track and the message “SLED OUT” is 
displayed on the fl uorescent indicator tube.

5.  Press the [CD 

u

] button, “LD ON” or “LD OFF” is displayed  

on the fl uorescent indicator tube. Each time [CD 

u

] button is 

pressed, laser diode on/off is changed over.

6.  To release this mode, press the [

?

/

1

] button.

Procedure:
1.  Turn on the set.
2.  Input the following signal from signal generator to FM antenna 

input directly.

Carrier frequency : A = 87.5 MHz, B = 98 MHz, C = 108 MHz
Deviation 

: 75 kHz

Modulation 

: 1 kHz

ANT input 

: 35 dBu (EMF)

Note:  Use 75 ohm coaxial cable to connect signal generator and the set. 

You cannot use video cable for checking.

 

Use signal generator whose output impedance is 75 ohm. 

3.  Set to FM tuner function and tune A, B and C signals.
4. Confi rm “TUNED” is lit on the display for A, B and C sig-

nals.

When the selected station signal is received in good condition, 
“TUNED” is displayed.

Note:
1.  CD Block is basically constructed to operate without adjustment.
2.  Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3.  Use an oscilloscope with more than 10 M

Ω impedance.

4.  Clean the object lens by an applicator with neutral detergent when the 

signal level is low than specifi ed value with the following checks.

5.  Check the focus bias check when optical pick-up block is replaced.

Procedure:
1.  Connect oscilloscope to TP121 (RFI) and TP124 (VC) on the 

CD board.

2.  Press the [

?

/

1

] button to turn the power on.

3.  Set disc (YEDS-18) on the disc tray and press the [CD 

u

] 

button to playback.

4. Confi rm that oscilloscope waveform is as shown in the fi gure 

below. (eye pattern)

 

A good eye pattern means that the diamond shape (

◊) in the 

center of the waveform can be clearly distinguished.