Self-Diagnostic; General; Test Mode Setting; Operation In Test Mode Setting - Sony MZ-R55 Service Manual

2-1. GENERAL

This set uses the self-diagnostic system in which if an error occurs
in playback/recording mode, the error is detected by the model
control and power control blocks of the microprocessor and infor-
mation on the cause is stored as history in EEPROM.
By viewing this history in test mode, it helps you to analyze a fault
and determine its location.

2-2. TEST MODE SETTING

There are two different methods to set the test mode:
1 Short BP801 (TEST) on the main board with a solder bridge
(connect pin @§ of IC801 to the ground). Then, turn on the
power.
main board
– (side B) –
IC503
BP801
IC509
C309
2 In the normal mode, use the keys on the unit to perform the
following operations:
Press and hold down ( and press the keys below in this turn:
+ n + n =n = n + n = n + n
= n P n P

2-3. OPERATION IN TEST MODE SETTING

When the test mode is set, the LCD shows repeated cycles of the
following display:
1) Unit LCD
ı
All ON
188 : 8 8
Ver ‚‚.8‚
Microprocessor
version
display
SECTION 2

SELF-DIAGNOSTIC

IC802
R818
All OFF
2) Remote controller LCD
888
Ver ‚.8‚
• Holding down P allows the current display to be maintained
while it being depressed.

2-4. RELEASING THE TEST MODE

For test mode set with the method 1:
Turn off the power and open the solder bridge on BP801 on the
main board.
For test mode set with the method 2:
Turn off the power.

2-5. SELF-DIAGNOSTIC MODE

1. Go into the test mode.
2. With the unit LCD indicators all flashing, press DISPLAY key
to go into the self-diagnostic mode.
1st ‚
3. Then, each time ) key is pressed, the reference information
display changes as given below.
1st ‚ XX
1st 1 ‚‚
1st 2 ‚‚
N ‚ XX
N 1 ‚‚
N 2 ‚‚
• Press = key to go back to the previous display.
– 5 –
ı
All ON
All OFF
Microprocessor
version
display
History code
Error indication code
‚‚
N-1 ‚ XX
N-1 1 ‚‚
N-1 2 ‚‚
N-2 ‚ XX
N-2 1 ‚‚
N-2 2 ‚‚
REC XXXX
1st ‚ XX (return)