Denon AVR-X3400H - Page 113

YES
YES
YES
YES
Check the I2C communication line. (ARC IC)
Check item(43). Check the I2C communication line :
Check the CPU.
Is the waveform of the TP near the ARC IC [U1007] correct (like
the one shown in the diagram) when the power is turned on?
U1007
AVSCL(R2152)
AVSDA(R2153)
ARC IC [U1007] is faulty.
Replace with a new device.
ARC IC [U1007] is faulty.
Replace with a new device.
Recheck from check item (1).
If it does not work, replace the PCB.
Check item(44). Check the I2C com-
munication line :
Check ARC IC [U1007] patterns as well
as soldering.
If there is no problem, go to the next
step.
Check the ARC IC.
Remove the damping resistor [R2152/R2153] of [U1007].
Is the "I2C" waveform correct?
Recheck from check item (1).
If it does not work, replace the PCB.
NO
YES NO
*The diagram shows an example.
(Signal patterns vary depending on the tim-
ing.)
Points for checking waveforms
- Crest value (3.3V normally)
- Signal change
- SCL frequency (400kHz normally)
Voltage scale : 1.0V/div
Time scale : 10us/div
113
Caution in
servicing
Electrical Mechanical Repair Information Updating