NEC MultiSync 20WGX2 Service Manual page 103

10. Power Board - No Power ON 10. Power Board - No Power ON
Check pow er cord (P801), signal Check pow
Check pin 8 of I808 have same pulse or not. Check pin 8 of I808 have same pulse or not.
Check pin 1 of T806 have same pulse or not. Check pin 1 of T806 have same pulse or not.
Check peak voltage of R840 triangle pulse is up to Check peak voltage of R840 triangle pulse is up to
Check T806, D817, C845, C857 have same short Check T806, D817, C845, C857 have same short
Check output voltage +5V is right or not Check output voltage +5V is right or not
O O K K
er cord (P801), signal cable, P802, cable, P802,
P803 are connected P803 are connected
right or not. right or not.
O O K K
Check C80 Check C80 1 i 1 is about s about DC DC 140V-330V or not. 140V-330V or not.
O O K K
Check C 853 is over 16V or Check C 853 is over 16V or not. not.
O O K K
O O K K
O O K K
1.5 volt or not. 1.5 volt or not.
O O K K
circuit, or the output +5V is over load circuit, or the output +5V is over load
O O K K
Check feedback circuit around I807 and Check feedback circuit around I807 and
the other component and repair them. the other component and repair them.
N N G G I I t i t is s n n o o t p t po o w w e e r b r b o o a a rd rd p p r r o o b b le le m m . .
Connect it right. Connect it right.
N N G G
N N G G
Check F801, D802, P801 and repair them Check F801, D802, P801 and repair them
Check D813, L810, I808, C853, ZD802 Check D813, L810, I808, C853, ZD802
N N G G
and repair them. and repair them.
Check peripheral component of I801 and Check peripheral component of I801 and
N N G G
repair them. repair them.
N N G G
Check Q 802, R840 and repai Check Q 802, R840 and repair them.
Check peak voltage of R840 triangle Check peak voltage of R840 triangle
N N G G
pulse is up to 0.85 volt or not. pulse is up to 0.85 volt or not.
N N G G R R e e p p a a i i r r t t h h e e m m . .
6 - 12 6 - 12
r them.