ViewSonic VX500PLUS-1 Service Manual page 46

4. No Sound (Test signal: 1rms sine waveform)
YES
Check that ICA1 Pin 3 is
approximately 9V
YES
Check ICA2 pin11
Pin15 signal is
FIG 19.
YES
Check ICA3 pin4, 6
is FIG20.
YES
Check ICA5, ICA6 pin4 is
about 5V
YES
ICA5 or ICA6 failure
ViewSonic Corporation
Check that ICA3 Pin 7 is approximately 12V
NO
Check ICA1 pin2
is about 5V
YES
NO
ICM10 failure
NO
Check that ICA4 Pin4 is
Low voltage
YES
Check ICA4
Pin5, 6, 7, 8 is12V
NO
ICA4 failure
NO
Failure point
1.ICA1 failure
2.ICM10 failure
Failure point
1. QA6 or QA7 failure
2. ICA3 failure
43
Confidential – Do Not Copy
Failure point
1.JA1 failure
2.ICM10 failure
NO
NO
VX500+-1