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When the results of check item (3-14.1.) are "NO"
(Detection of 5V is not OK)
Check the +5V voltage. (HDMI IN5 - 7)
Check item(3-14.3.).
Check the +5V voltage.
Does the test point near HDMI input terminal [N2400/N2401/N2402] indicate 5V?
N2402
N2401
N2400
HDMI 7
HDMI 6
HDMI 5
[CD]
[AUX2]
[MEDIA PLAYER]
5V
5V
5V
YES
HDMI Switcher1 [U2401] is faulty.
Replace with a new device.
Recheck from
check item (3.2.)
If it does not work, replace the PCB.
NO
Check for a short circuit in the 5V line and the 5V
Switch IC [U2400].
If there is no problem, the HDMI Switcher1
(U2401) or the 5V Switch IC [U2400] is faulty
Replace with a new device.
When the results of check item (3-14.2.) are
(Detection of DDC is not OK.)
Check the DDC line. (HDMI IN5 - 7)
Check item(3-14.4.).
Check the DDC line :
Are waveforms of "DDCCL" and "DDCDA" observed at the test point near the HDMI input terminal
[N2400/N2401/N2402]?
N2402
N2401
HDMI 7
HDMI 6
[CD]
[AUX2]
DDCSCK
DDCSDA
YES
HDMI Switcher1 [U2401] is faulty.
Replace with a new device.
Recheck from
check item (3.2.)
If it does not work, replace the PCB.
119
"00 or
04"
less than 100KHz
5V
N2400
HDMI 5
[MEDIA PLAYER]
5V
This diagram shows an example of the DDC commu-
nication waveform.
-The high level voltage is 5V.
-The frequency of the DDC CLK is 100kHz or less.
Check at each test point.
Voltage scale : 2.0V/div
Time scale : 40us/div
NO
Check for a short circuit in the DDC line.
If there is no problem, the HDMI Switcher1
[U2401] is faulty.
Replace with a new device.
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