Denon AVR-X2500H Service Manual page 105

3-8. Error Code H1-08 failure detection procedure
Checking device. [U1073 : CS49844A]
Check the power supply voltage.
Check item(30). Check the power supply voltage.
:
Does the power supply voltage of the DSP [U1073]
indicate the appropriate voltage (1.0V, 3.3V)?
The test points are as follows.
1.0V
3.3V
C2138
U1073
C2102
YES
DSP [U1073] is faulty.
Replace with a new device.
Recheck from check item (1).
If it does not work, replace the PCB.
NO Check item(31). Check the power supply voltage.
:
Check the power supply components [U1067,
U1068, U1078] on the substrate and peripheral
pattern.
If there is no problem, remove the DSP [U1073]
from the substrate and measure the voltage at
the test point of check item (30).
Is the voltage correct (1.0V or 3.3V)?
YES NO
The power supply circuit is faulty.
Replace the PCB.
Checking the reset waveform.
Check item(32). Checking the reset :
Check the CPU.
Is the waveform of the TP near the DSP [U1073] correct (like the
one shown in the diagram) when the power is turned on?
U1073
32 pin
YES NO
Check the reset circuit between CPU [U1018] and DSP [U1073].
If there is no problem, the DSP [U1073] is faulty.
Replace with a new device.
Recheck from check item (1).
If it does not work, replace the PCB.
105
Examples of confirmation waveform
Voltage scale：1.0V/div
Time scale：20ms/div
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