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•
Transmit the commands "MUTE" - "062500" - "OK" with a
normal RC. The complete error buffer is shown. Take
notice that it takes some seconds before the blinking LED
starts.
•
Transmit the commands "MUTE" - "06250x" - "OK" with a
normal RC (where "x" is a number between 1 and 5). When
x= 1 the last detected error is shown, x= 2 the second last
error, etc.... Take notice that it takes some seconds before
the blinking LED starts.
•
"DIAGNOSE X" with the DST (where "x" is a number
between 1 and 5). When x= 1 the last detected error is
shown, x= 2 the second last error, etc.... When x = 0 all
errors are shown.
5.7
Protections
Note: With Samsung PDP displays (SDI V4) boards it is
possible that for some errors the blinking LED procedure does
not start immediately (e.g. error 18). When the error occurs, the
TV goes to protection and it is possible that you have to wait 30
seconds before the blinking LED procedure starts.
5.7.1
Introduction
This chassis has only one microprocessor (OTC), which
remains active during Stand-by. This because power of the
microprocessor and the attached memory chip set is coming
from the 3V3 supply, which is derived from the 5V Stand-by-
circuitry. Therefore, in both Power-on as in Stand-by mode, the
microprocessor is connected to this power supply.
If a fault situation is detected, an error code will be generated
and if necessary, the TV is put in protection mode. The
protection mode is indicated by the blinking of the front LED at
a frequency of 3 Hz (or by a coded blinking in special cases).
The content of the error buffer can be read via the service menu
(SAM), the blinking LED procedure or via DST/ComPair.
To get a quick diagnosis, this chassis has three service-modes
implemented:
•
The Customer Service Mode (CSM).
•
The Service Default Mode (SDM). Start-up of the TV in a
predefined way.
•
The Service Alignment Mode (SAM). In this mode, items
of the TV can be adjusted via a menu.
You can activate both SDM and SAM modes via the "service
pads" on the SSB (see figure "Service pads"), via an RC-
transmitter (DST or standard RC), or via ComPair. It is not
possible to activate the SAM in "stand-by"; the TV has to be in
"normal operation" mode.
The "Protection Diagram" shows the structure of the protection
system. See diagram below.
DC_PROT (from audio)
+8V_CON
+5V_CON
TUNER
FAST I2C BUS BLOCKED
SLOW I2C BUS BLOCKED
EPLD
+
FBX
+
3D COMB
Figure 5-8 Protection diagram
Service Modes, Error Codes, and Fault Finding
IRQ-DIGITAL (98)
+8V SENSE (105)
+5V SENSE (106)
OTC
DC/DC
I2C
PROTECTION
E_14650_032.eps
There are several types of protections:
2
•
I
C related protections.
•
OTC related protections (via polling on I/O pins or via
algorithms).
•
Hardware protection
All protections are explained below.
2
5.7.2
I
C Related Protections
In normal operation, some registers of the I
are refreshed every 200 ms. During this sequence, the I
buses and the I
2
An I
C protection will take place if the SDA and SCL lines are
short-circuited to ground, or to each other. An I
occur, if the power supply of the IC is missing.
DC/DC protection: When a 3V3 supply is short-circuited, the
DC/DC converter switches "off" and goes in protection. The
FBX, EPLD IC, and 3D comb IC have no supply voltage and
give no acknowledge. In this case, the TV should go into
protection. An error code is written in the NVM: DC/DC error.
FBX protection: the FBX protection is not available any more.
It is replaced by the DC/DC protection.
5.7.3
OTC Related Protections
If a protection is detected at an OTC input, the OTC will start to
scan all protection inputs every 200 ms for 5 times. If the
protection on one of the inputs is still active after 1 s, the
microprocessor will put the TV in the protection mode. Before
the scanning is started, a so-called "ESD refresh" is carried out.
This is done, because the interrupt on one of the inputs is
possibly caused either by a flash or by ESD. As a flash or ESD
can influence IC settings, the HIP, MSP, 3D Comb and wireless
module (not used in this set) are initialised again, to ensure the
normal picture and sound conditions of the TV.
8 V and 5 V protections: The microprocessor senses the
presence of the 8 V and 5 V (via the "+5V_CON" and
"+8V_CON" lines). If one (or both) of these voltages is (are) not
present, an error code is stored in the error buffer of the NVM,
and the TV is put in the protection mode.
Audio Supply protection: The OTC senses if the audio
module is in protection via IRQ-DIGITAL (pin 98 of OTC). If this
is the case, the OTC puts the TV in protection.
5.7.4
Hardware Protection
Short-circuiting the 3V3 supply from the DC/DC converter will
shut down the DC/DC converter. The absence of the 3V3
supply line is also sensed via I
protection above), this is useful if there is something wrong in
the detection circuit of the DC/DC converter.
Audio DC Protection: This protection occurs when there is a
DC voltage on the speakers. In that case, the Main Supply is
switched "off". The Stand-by Supply is still working. For the
Samsung SDI V4 displays, all internal supplies (except the
5V2), are switched "off" and the LED on the Samsung SDI V4
display (on PSU Alarm board) blinks 11 times., which means
there is an overvoltage protection.
Repair tip: If there is an audio DC protection (DC voltage on
your speakers), you will probably see error 18 blink. To be sure
this is an audio DC protection, disconnect the cable between
the SSB and the audio PWB and also the cable between the
Main Supply and the Audio PWB. If the TV starts up, it is very
likely that there is DC on the speakers. Check, and replace if
necessary, the audio amplifiers.
170604
Note: It is also possible that you have an Audio DC Protection
because of an interruption in one or both speakers (the DC
FTP2.4A AA
5.
2
C controlled ICs
2
C ICs are checked.
2
2
C (see description Audio Supply
EN 21
2
C
C error will also
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