YES
YES
YES
Check the I2C communication line. (HDMI Rx/TX)
Check item(8).
Check the I2C communication line :
Check the CPU.
Is the "
I2C
" waveform of the TP HDMI Rx/Tx [
IC721
] correct (like
the one shown in the diagram) when the power is turned on?
IC720
P_CK
P_DA
HDMI Rx/Tx [
IC721
] is
faulty. Replace with a
new device.
HDMI SW [
IC701
] is
faulty. Replace with a
new device.
CPU [
IC751
] is faulty.
Replace with a new
device.
HDMI Rx/Tx[
IC721
] is faulty.
Replace with a new IC.
Recheck from
check item (1).
If it does not work, replace the PCB.
Check item(9).
Check the I2C commu-
nication line :
Check HDMI Rx/Tx [
IC721
], CPU[
IC751
]
patterns as well as soldering.
If there is no problem, go to the next
step.
Check the HDMI SW.
Remove the damping resistor
[
R7147/R7149
] of [
IC701
].
Is the "
I2C
" waveform correct?
Recheck from
check item (1).
If it does not work, replace the PCB.
Check the HDMI Rx/Tx.
Remove the damping resistor
[
R7229
/
R7231
] of [
IC721
].
Is the "
I2C
" waveform correct?
NO
NO
YES
YES
NO
*The diagram shows an example.
(Signal patterns vary depending on the tim-
ing.)
Points for checking waveforms
- Crest value (3.3 V normally)
- Signal change
- SCL frequency (400 kHz normally )
Voltage scale：1.0V/div
Time scale：10us/div
81
Caution in
servicing
Electrical
Mechanical
Repair Information
Updating
Summary of Contents for AVR-S730H
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