Marantz NR1508 - Page 95

When the results of check item (37) are "00 or 04"
(Detection of DDC is not OK.)
Check item(39). Check the DDC LineHPD line :
Are waveforms of "CK" and "DA" observed at the test point near the HDMI input terminal [N1015/
N1016/N1017]?
N1017
HDMI 3
[GAME]
N1015
HDMI 1
[CBL/SAT]
N1016
HDMI 2
[Blu-ray/DVD]
DDCSCK
DDCSDA
Check the DDC line. (HDMI SW)
HDMI SW [U1024] is faulty.
Replace with a new device.
Check for a short circuit in the DDC line.
If there is no problem, the HDMI SW [U1024] is
faulty.
Replace with a new device.
Recheck from check item (2).
If it does not work, replace the PCB.
YES NO
less than 100KHz
5V
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 100 KHz or less.
Check at each test point.
Voltage scale：2.0V/div
Time scale：40us/div
When the results of check item (36) are "00"
(Detection of 5V is not OK)
Check item(38). Check the +5V voltage :
Does "+5V" at the following test point indicate 5 V? [N1015/N1016/N1017]
N1017
HDMI 3
[GAME]
N1015
HDMI 1
[CBL/SAT]
N1016
HDMI 2
[Blu-ray/DVD]
+5V+5V+5V
Check the +5V voltage. (HDMI SW)
HDMI SW [U1024] is faulty.
Replace with a new device.
Check for a short circuit in the 5 V line and the 5
V Switch IC [U1025].
If there is no problem, the HDMI SW [U1024] is
faulty.
Replace with a new device.
YES NO
Recheck from check item (2).
If it does not work, replace the PCB.
95
Caution in
servicing
Electrical Mechanical Repair Information Updating