Philips FTL2.4A Service Manual Download

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Service Modes, Error Codes, And Fault Finding

EN 19

FTL2.4A AA

5.6

The Blinking LED Procedure

5.6.1

Introduction

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 SDM is activated, the front LED will show (blink) the
contents of the error-buffer. Error-codes > 10 are shown as
follows:
–

A long blink of 750 ms (which is an indication of the decimal
digit),

–

A pause of 1.5 s,

–

“n” short blinks (where “n” = 1 - 9),

–

When all the error-codes are displayed, the sequence
finishes with a LED blink of 3 s,

–

The sequence starts again.

Note:

For error codes >100, the first two digits (hundred-and-

ten) are considered as one digit (one long blink)

Example:

Error 12 9 6 121 0.

After activation of the SDM, the front LED will show:
–

1 long blink of 750 ms (which is an indication of the decimal
digit) followed by a pause of 1.5 s,

–

2 short blinks followed by a pause of 3 s,

–

9 short blinks followed by a pause of 3 s,

–

6 short blinks followed by a pause of 3 s,

–

12 long blinks of 750 ms (which is an indication of “120”)
followed by a pause of 1.5 s,

–

1 short blink followed by a pause of 3 s,

–

1 long blink of 3 s to finish the sequence,

–

The sequence starts again.

Note

: If errors 1, 6, or 18 occur, the LED always gives the last

occurred error even if the TV is NOT in service mode.

5.6.2

How To Activate

Use one of the following methods:
•

Activate the SDM (only via soldering pads marked “SDM”
on SSB, see figure “Service pads”). The blinking front LED
will show the entire contents of the error buffer (this works
in “normal operation” mode and in “protection” 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.

•

“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

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.

Figure 5-6 Protection diagram

There are several types of protections:
•

C related protections.

•

OTC related protections (via polling on I/O pins or via
algorithms).

•

Hardware protection

All protections are explained below.

5.7.2

C Related Protections

In normal operation, some registers of the I

C controlled ICs

are refreshed every 200 ms. During this sequence, the I

buses and the I

C ICs are checked.

An I

C protection will take place if the SDA and SCL lines are

short-circuited to ground, or to each other. An I

C error will also

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.

DC_PROT (from audio)

IRQ-DIGITAL (98)

+8V_CON

+8V SENSE (105)

+5V_CON

+5V SENSE (106)

OTC

TUNER

FAST I2C BUS BLOCKED

SLOW I2C BUS BLOCKED

DC/DC

I2C