Denon AVR-X2500H Service Manual page 107

3-9. Error Code H1-12 failure detection procedure
Checking device. [U1040 : PCM9211]
Check the power supply voltage.
Check item(35). Check the power supply voltage.
:
Does the power supply voltage of the DIR [U1040]
indicate the appropriate voltage (3.3V)?
The test points are as follows.
3.3V
U1040
C2059
YES
DIR [U1040] is faulty.
Replace with a new device.
Recheck from check item (1).
If it does not work, replace the PCB.
NO Check item(36). Check the power supply voltage.
:
Check the power supply components [U1069,
U1078] on the substrate and peripheral pattern.
If there is no problem, remove the DIR [U1040]
from the substrate and measure the voltage at
the test point of check item (35).
Is the power supply voltage correct (3.3 V)?
YES NO
The power supply circuit is faulty.
Replace the PCB.
Checking the reset waveform.
Check item(37). Checking the reset :
Check the CPU.
Is the waveform of the TP near the DIR [U1040] correct (like the one
shown in the diagram) when the power is turned on?
U1040
34 pin
YES NO
Check the reset circuit between CPU [U1018] and DIR [U1040].
If there is no problem, the DIR [U1040] is faulty.
Replace with a new device.
Recheck from check item (1).
If it does not work, replace the PCB.
107
Examples of confirmation waveform
Voltage scale：1.0V/div
Time scale：20ms/div
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