Service Test Program - Philips AZ7381 Service Manual

SERVICE TEST PROGRAM

1. PRELIMINARY SETUP
• To enter the service test program hold the keys "MODE" and
"STOP" depressed while turning POWER ON (i.e. connecting
the AC/DC adaptor or inserting batteries).
• The display shows the software version of the built-in
microprocessor (i.e. "S- "). Versions are counted from "
19
onwards; that means the higher the number the newer the
software.
• The program is now in the main menu – various tests can be
entered by pressing the corresponding buttons (see flow chart
on next page or detailed description of test programs below).
• To exit the service test program disconnect the set from the
power source.
2. DISPLAY TEST
Purpose: Check functionality of display and display driver.
• To enter the display test start service test program and press
the "NEXT" button.
• The display shows test pattern1. All segments are activated for
finding open circuits (see flow chart on next page).
• To jump to the next pattern press the "NEXT" button.
• The display shows test pattern2. All alternate pins (2, 4, ...) are
activated for finding short circuits (see flow chart on next page).
• To jump back to test pattern1 press the "NEXT" button, to exit
the display test and return to the main menu press the "STOP"
button.
3. KEY TEST
Purpose: Check operation of keys.
• To enter the key test start service test program and press the
"MODE" button.
• The display shows "--".
• Hold key depressed and check corresponding key code on the
display. Key codes can be found in table1 (see flow chart on
next page).
• To exit the key test and return to the main menu press the
"STOP" button.
4. PLAYBACK TEST WITH ERROR ANALYSIS
Purpose: Analyse errors that occur during playback and search
for intermittent failures.
• To enter the playback test start service test program and press
the "DBB" button. Note that the playback test can only be
entered if the CD-door is closed.
• The set now reads the TOC and switches to stand-by.
• Press the "PLAY" button to start the error analysis.
As long as the playback is free of errors the display shows track
and time information like in normal play-mode.
In case of an error a corresponding error code will be displayed.
The meaning of this error code can be found in table2 (see flow
chart on next page).
Note: Errors can either be "fatal" or "non fatal" . Fatal errors
always stop the playback, non fatal errors only cause a
short interruption of the music. Fatal errors are displayed
as long as the set is connected to the power source, non
fatal errors are displayed until a new error occurs or a
button is pressed.
• To stop the playback test disconnect the set from the power
source.
5. SERVO TEST
Purpose: Check door switch and inner switch, movement of
slide and acceleration of discmotor.
• To enter the servo test start service test program and press the
"PLAY" button.
• The display shows "S xy ".
" x " indicates state of door switch;
" y " indicates state of inner switch.
x,y = "0" means switch is closed; "1" means switch is open.
CS 46 462
3-1
• To move slide outside hold the "NEXT" button depressed.
• To move slide inside hold the "PREV" button depressed.
• To accelerate the discmotor clockwise hold the "MODE" button
depressed.
• To accelerate the discmotor counter-clockwise hold the
"PROG" button depressed.
• To enter the focus test press the "PLAY" button, to exit the
servo test and return to the main menu press the "STOP"
"
00
button.
6. FOCUS TEST
Purpose: Check movement of lens and operation of focus servo.
• The focus servo loop is switched on and the set starts
searching the focus ("focus ramping"). As soon as the focus
has been found the focus servo loop is closed and the state of
the focus is monitored continuously.
If the focus is OK the display shows " F", else "-F".
• When the disc is turned manually "focus noise" is audible.
• To move slide outside hold the "NEXT" button depressed.
• To move slide inside hold the "PREV" button depressed.
• To accelerate the discmotor clockwise hold the "MODE" button
depressed.
• To accelerate the discmotor counter-clockwise hold the
"PROG" button depressed.
• In case the focus is OK the discmotor test can be entered by
pressing the "PLAY" button, to exit the focus test and return to
the main menu press the "STOP" button.
7. DISCMOTOR TEST
Purpose: Check speed regulation of discmotor.
• The speed regulation is switched on and the discmotor starts
rotating. If the speed reaches 75% of the nom. speed the
display shows " d", else "-d".
• In parallel also the state of the focus is monitored continuously
(display " F" or "-F").
• In case the disc speed is OK and the focus is OK the radial test
can be entered by pressing the "PLAY" button, to exit the
discmotor test and return to the main menu press the "STOP"
button.
8. RADIAL TEST
Purpose: Check if radial loop locks and an audio signal is
audible at the headphone output.
• The radial servo loop is switched on, mute is released and the
audio signal is audible. If the system is on track the display
shows " r", else "-r".
• In parallel also the disc speed (display " d" or "-d") and the
state of the focus (display " F" or "-F") are monitored
continuously.
Note: In case of radial errors the audio output is muted and
muting is not released automatically when the systems
recovers from the error. "-r" remains on the display.
To open mute again press the "NEXT" or "PREV" button.
• To jump 10 tracks outside press the "NEXT" button.
• To jump 10 tracks inside press the "PREV" button.
• To exit the radial test and return to the main menu press the
"STOP" button, to exit the service test program disconnect the
set from the power source.
Important remark:
In radial test mode data to the DRAM is written at 1.2 times the
nominal speed, and read from the DRAM at nominal speed.
Because writing is done faster than reading the DRAM gets full
after a certain time.
In normal play mode the system would now wait until the DRAM
is partly emptied again, jump backwards and resume filling at the
last written position. However, in radial test mode the jumps
would disturb measurements on the radial servo loop.
Therefore this function has been disabled and filling restarts
immediately from the current position of the pick-up unit. As a
result "jumps" are audible during playback.