Acer AL707 - Page 24

23
II. TROUBLE SHOOTING BLOCK DIAGRAM
A) NO POWER:
FAIL
PASS FAIL
PASS
FAIL
PASS
B) HIGHT VOLTAGE PROTECTION:
FAIL
PASS
CHECKED ON FUSE
F1 Vin=12
TO CHANGED
F1= 4.0A/63V
TO CHECKED Q4 & Q6
VOUT = 9V
TO CHECKED L1/L2
INPUT 9V TO L1 OR L2
TO CHANGED
CH1: Q4/Q3/Q11
CH2: Q5/Q6/Q12
TO CHANGED
CH1: Q7/Q8/D12/PT1
CH2: Q9/Q10/C13/PT2
FUNCTION TEST OK !
1. SHORT R30 & OPEN LOAD
2. TEST PT1 OR PT2 OUTPUT PIN 7 H.V
VOLTAGE Vh=1600 ±100V rms
TO CHANGE ON PT1
OR PT2
FUNCTION TEST OK!