Philips L04HE Service Manual page 16

EN 16 5. L04HE AA
Picture Ok, No Sound
Picture Ok,
No Sound
Check IF output of
tuner, pin 11
CVBS
No
present?
Yes
Check SAW filter output
(pin 4&5)
EU/AP/CH (QSS)- 1001
NA/LA/AP INT - 1002
Output Ok? No
Yes
Check other
functional area
Figure 5-10 Fault finding tree "Picture ok, no sound"
Unable To Perform Tuning
Unable to
perform tuning
Enter SDM
check optionbyte 1 Incorrect
Correct
Check if tuner
Supply Voltage 5V
pin 7
Yes
Check Tuner
Supply Voltage
Check I 2 C at pin
4 & 5 and tuner
Ok
Check other
functional area
Figure 5-11 Fault finding tree "Unable to perform tuning"
Service Modes, Error Codes, and Fault Finding
Refer to fig.
"Power Supply:
Set not working"
Replace SAW
filter
E_14480_063.eps
170204
Enter SDM and change
to the appropriate byte
Check I 2 C
Check Power
No
Supply circuit
No
33V
Yes
Not Ok
Not Ok
I 2 C
Not Ok
E_14480_064.eps
5.8.6 Controller
Below are some guidelines for troubleshooting of the Micro
Controller function. Normally Micro Controller should be
checked when there is a problem of startup.
1. Check that both +3.3 V_dc and +1.8 V_dc are present.
2. Check that crystal oscillator is working.
3. Check that Power Good signal is at "high" logic, normal
operation.
4. Check that HERCULES is not in standby mode. Pin 15 of
HERCULES should be 0 V_dc.
5. Make sure H-drive pulse is there. This can be checked at
resistor R3239. If H-drive does not exist, remove resistor
R3239 to check if there is loading.
Note: When the set shuts down after a few second after power
"on", the main cause is that Vg2 not aligned properly, try
adjusting Vg2 during the few seconds of power "on".
5.8.7 Video Processing
No Picture
When "no picture in RF", first check if the microprocessor is
functioning ok in section "Controller". If that is ok, follow the
next steps.
When "no picture in AV", first check if the video source
selection is functioning ok in section "Source Selection". If that
is ok, follow the next steps.
1. Check that normal operating conditions are met.
2. Check that there is video signal at pin 81. If no video,
demodulator part of the HERCULES is faulty, replace with
new HERCULES.
3. If video signal is available at pin 81, check pin 56, 57, and
58 for the RGB signal.
4. If signal is not available, try checking the BRIGHTNESS
and/or CONTRAST control, and make sure it is not at zero.
5. If still with the correct settings and no video is available,
proceed to the CRT/RGB amplifier diagram.
For sets with TDA9178, follow steps below:
1. Put Option Byte 2 bit 4 to "0"; if video signal is not available,
then check fault finding section "Controller", Section
"Source Selection", and steps above.
2. If video is available but not correct, put Option Byte 2 bit 4
to "1", then check if LTI panel is present. If not, put LTI
panel in the main chassis (connector 1221).
3. If LTI panel is in main chassis, check cable between LTI
panel and main chassis (position is 1206). If it is
Replace
connected, then the LTI panel is faulty, replace it.
Tuner
For sets with Scavem, and Scavem does not work, follow steps
below:
1. Check Scavem coil connector (position is 1361) if
connected; if not, connect it.
Not Ok
2. If connected, check NVM "bit storage" byte 1 bit 7; if it is not
"1", set it to "1".
3. If it is "1", then check the data of the NVM addresses as in
the next table. If the data is not correct, then set these
addresses to diagram values.
4. If it still not works, track Scavem output from pin64 of
Tuner
HERCULES to CRT panel.
170204
Table 5-3 NVM default values for Scavem
Description
SPR, WS
VMA, SVM
NVM_SOC_SMD
Address (dec) Address (hex) Value (hex)
140 8C 00
141 8D 32
142 8E 03