Service Modes, Error Codes, and Fault Finding
EN 30 JL2.1E AA5.
5.6 The Blinking LED Procedure
5.6.1 Introduction
The blinking LED procedure can be split up into two situations:
• Blinking LED procedure in case of a protection detected by
the stand-by processor. In this case the error is
automatically blinked. This will be only one error, namely
the one that is causing the protection. Therefore, you do
not have to do anything special, just read out the blinks. A
long blink indicates the decimal digit, a short blink indicates
the units.
• Blinking LED procedure in the “on” state. Via this
procedure, you can make the contents of the error buffer
visible via the front LED. This is especially useful for fault
finding, when there is no picture.
When the blinking LED procedure is activated in the “on” state,
the front LED will show (blink) the contents of the error-buffer.
Error-codes > 10 are shown as follows:
1. “n” long blinks (where “n” = 1 - 9) indicating decimal digit,
2. A pause of 1.5 s,
3. “n” short blinks (where “n”= 1 - 9),
4. A pause of approx. 3 s.
5. When all the error-codes are displayed, the sequence
finishes with a LED blink of 3 s,
6. The sequence starts again.
Example: Error 12 9 6 0 0.
After activation of the SDM, the front LED will show:
1. 1 long blink of 750 ms (which is an indication of the decimal
digit) followed by a pause of 1.5 s,
2. 2 short blinks of 250 ms followed by a pause of 3 s,
3. 9 short blinks followed by a pause of 3 s,
4. 6 short blinks followed by a pause of 3 s,
5. 1 long blink of 3 s to finish the sequence,
6. The sequence starts again.
5.6.2 How to Activate
Use one of the following methods:
• Activate the SDM. The blinking front LED will show the
entire contents of the error buffer (this works in “normal
operation” mode).
• 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.
5.7 Protections
5.7.1 Software Protections
Most of the protections and errors use either the stand-by
microprocessor or the VIPER controller as detection device.
Since in these cases, checking of observers, polling of ADCs,
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, +5V,
+8V6, +1.2V, +2.5V and +3.3V.
• Protections related to breakdown of the safety check
mechanism. E.g. since a lot of protection detections are
done by means of the VIPER, failing of the VIPER
communication 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 optimise 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. As the
observers are only used during start-up, they are described in
the start-up flow in detail (see paragraph “Stepwise Start-up").
5.7.2 Hardware Protections
There is one hardware protection in this chassis: “Audio DC
Protection”. This protection occurs when there is a DC voltage
on the speakers. In that case the main supply is switched "off",
but the stand-by supply is still working.
In case of LCD supplies, the 12V supply will drop. This will be
detected by the stand-by processor, which will start blinking the
12 V error (error 12).
Repair Tips
• If there is an audio DC protection (DC voltage on your
speakers), you will probably see error 12 blink in case of
LCD TVs. To be sure there 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
voltage on the speakers. Check, and replace if necessary,
the audio amplifiers.
• 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).
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