Acer AL1713bm Service Manual page 31

3. QPI PCBA Troubleshooting
3.1
Is there DC12V & DC5V at
#6 & #8 of CN852?
NO YES
Is the voltage at C854 in
the range of 127V~339V?
YES
Is the voltage at #3 of U850
16V?
YES
Is the voltage at #6 of U850
0.8V?
YES
Is the voltage at #6 of T850
38V?
YES
Check Q851
Check F850 & D850
NO
Check R855, R857, R852
NO
Check R859
NO
Check D853, D854
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