Matsui 1410R, Service Manual

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11
FIG.7.2
Error messages
The microcomputer also detects errors in circuits connected
to the I
2 C (Inter IC) bus. These error messages are
communicated via OSD (On Screen Display) and a flashing
LED.
Note: After replacing the microcomputer first solder the
shielding before testing the set. This is needed as the
shielding is used for earth connection.
If this is not done the set can switch into protection mode
(see description of the SMPS).
Repair facilities
Test points
The CTN chasis is equipped with test points, TP1, TP2, etc
in the ser vice printing on the component side of the
monoboard.
Using these test points it is possible to set a quick diagnosis
on the top of the monoboard.
Functional blocks
On both the service printing on the copper and the component
side, functional blocks are given. These blocks indicate the
functionaly of that specific part of the circuit.
Service Default Mode
The CTN software contains a "Service Default Mode" .
To activate this mode the service pin of the microcomputer
(pin 7-IC7600) should be short-circuited to earth while
switching on the set with the mains switch (shorting pin 7
can be done on the copper side via the 2 copper squares or
on the component side by pin 7 and the shielding of the µC)
When the set in the Service Default Mode and "S" appears
on the screen.
In the Service Default Mode the set is in a pre-defined mode
In this mode all analog settings (volume, contrast, brighness
and saturation) are in the mid position and the set is tuned to
program number 1.
The Service Default Mode is left via switching off the set by
the mains switch or via standby on the remote control.
Error Error Possible defect-
message description tive component
F1 en OSD y Error interno µC IC7600
LED parpadea
F2 en OSD y Error Eeprom IC7685
LED parpadea