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EN 22
5.
LC9.3L LA
5.6
Fault Finding and Repair Tips
Notes:
•
It is assumed that the components are mounted correctly
with correct values and no bad solder joints.
•
Before any fault finding actions, check if the correct
options are set.
5.6.1
Software Protections
Most of the protections and errors use either the stand-by or the
micro processor as detection device. Since in these cases,
checking of observers, polling of ADCs, and filtering of input
values are all heavily software based, these protections are
referred to as software protections.
There are several types of software related protections, solving
a variety of fault conditions:
•
Protections related to supplies: check of the 12V.
•
Protections related to breakdown of the safety check
mechanism. E.g. since the protection detections are done
by means of software, failing of the software will have to
initiate a protection mode since safety cannot be
guaranteed any more.
Remark on the Supply Errors
The detection of a supply dip or supply loss during the normal
playing of the set does not lead to a protection, but to a cold
reboot of the set. If the supply is still missing after the reboot,
the TV will go to protection.
Protections during Start-up
During TV start-up, some voltages and IC observers are
actively monitored to be able to optimize the start-up speed,
and to assure good operation of all components. If these
monitors do not respond in a defined way, this indicates a
malfunction of the system and leads to a protection.
5.6.2
Hardware Protections
The only real hardware protection in this chassis is (in case of
an audio problem) the audio protection circuit that will trigger
the uP to switch "off" the TV.
Repair Tip
•
It is also possible that you have an audio DC protection
because of an interruption in one or both speakers (the DC
voltage that is still on the circuit cannot disappear through
the speakers).
Caution: (dis)connecting the speaker wires during the ON
state of the TV at high volume can damage the audio
amplifier.
5.6.3
Logging
When something is wrong with the TV set (f.i.the set is
rebooting) you can check for more information via the logging
in Hyperterminal. The Hyperterminal is available in every
Windows application via Programs, Accessories,
Communications, Hyperterminal. Connect a "ComPair UART"-
cable (3138 188 75051) from the service connector in the TV to
the "multi function" jack at the front of ComPair II box.
Required settings in ComPair before starting to log:
- Start up the ComPair application.
- Select the correct database (open file "Q549.3E LA", this will
set the ComPair interface in the appropriate mode).
- Close ComPair
After start-up of the Hyperterminal, fill in a name (f.i. "logging")
in the "Connection Description" box, then apply the following
settings:
1. COMx
2. Bits per second = 115200
3. Data bits = 8
4. Parity = none
2010-Mar-26
Service Modes, Error Codes, and Fault Finding
5.6.4
5.6.5
5.7
5.7.1
5.7.2
5. Stop bits = 1
6. Flow control = none
During the start-up of the TV set, the logging will be displayed.
This is also the case during rebooting of the TV set (the same
logging appears time after time). Also available in the logging
is the "Display Option Code" (useful when there is no picture),
look for item "DisplayRawNumber" in the beginning of the
logging. Tip: when there is no picture available during
rebooting you are able to check for "error devices" in the
logging (LAYER 2 error) which can be very helpful to determine
the failure cause of the reboot. For protection state, there is no
logging.
Display option code
Caution: In case you have replaced the SSB, always check the
display option code in SAM, even if you have picture. With a
wrong display option code it is possible that you have picture,
but that in certain conditions you have unwanted side-effects.
Trouble Shooting Tuner section
When there is no picture in analog RF mode:
1. Check whether picture is present in AV mode. If not, tuner
section is okay. Check video processing section.
2. Check if option settings are correct.
3. Check if 5 and 33 V supplies are available.
2
4. Check if the I
C lines are working correctly (3.3 V).
5. Manually store a known channel and check if there is IF
output at tuner pin 11. If not, tuner is faulty.
6. Feed in 105 dBuV at tuner pin 11 and check whether there
is CVBS output from IF demodulator IC. If not, IF
demodulator might be faulty. Check components in this
area.
Software Upgrading
Introduction
It is possible for the user to upgrade the main software via the
USB port. This allows replacement of a software image in a
stand alone set, without the need of an E-JTAG debugger. A
description on how to upgrade the main software can be found
in the DFU.
Important: When the NAND-Flash must be replaced, a new
SSB must be ordered, due to the presence of the security keys!
(copy protection keys, MAC address, ...).
Perform the following actions after SSB replacement:
1. Set the correct option codes (see sticker inside the TV).
2. Update the TV software => see the DFU for instructions.
3. Perform the alignments as described in chapter 6.
4. Check in CSM if the HDMI key, MAC address.. are valid.
For the correct order number of a new SSB, always refer to the
Spare Parts list on the Philips Service web portal!
Software Upgrade
SW versions can be divided in three types:
•
SW that can not crash the working of the set.
–
EDID NVM. If the download fails, the set is still running
and the download can start again.
–
Main NVM: If the download fails the default NVM value
can be loaded. NVM can be loaded via USB, be aware
PCBA alignments stored in NVM will not be overridden.
•
SW that is "fool proof": There is a backup version, a main
interruption during upgrade shall not crash the normal
working, a new upgrade can be started.
–
Main SW image: Upgradable via USB.
–
Standby SW.
–
ARM Ambilight (if applicable): Upgradable via USB.
•
SW that is not "fool proof".
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