5. Troubleshooting (continued)

5.8 Checking the resolution change IC movement

ACER G24

 

27

Go to cover page

Is there +3.3V

Supplied on I314 pin107,

pin48, pin61, pin250, pin12, pin70, pin170, pin184, pin203, pin216, pin236, pin252, pin20, pin28, pin38, pin19, pin37,

pin131?

OK

Is there +1.8V

supplied on I314 pin16, pin22, pin50, pin2, pin78, pin96, pin143, pin160, pin181,

pin225

OK

Is 14.318MHz

clock input to I314 pin35 and pin36 at TTL level during power on?

OK

Is +3.3V supplied to I314 pin9 at low level (Reset again)?

OK

Failure Point

I314 is defected.

 

 

 

Proceed to “5.9 Checking the DC/DC converter

NG

 

 

 

 

circuit” section

 

 

 

 

 

 

 

 

 

 

Proceed to “5.9 Checking the DC/DC converter

NG

 

 

 

 

circuit” section

 

 

 

 

 

 

 

 

 

Is 14.318MHz clock output

Failure Point

 

 

 

NG

 

from X302 pin1 at TTL level

 

 

 

 

X302 is defected.

 

 

 

 

 

 

 

during power on?

 

 

 

 

 

 

 

 

Failure Point

Print wire is broken between X302 pin1 and I314, pin36

NG

 

 

 

 

 

 

 

 

Failure Point

 

 

 

Check the output

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

of 3.3V “H” pulse from

 

NG

 

 

I306 is defected.

 

 

 

 

 

 

 

 

I306 pin12

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

OK

 

 

 

 

 

 

Failure Point

Print wire is broken between I306 pin12 and I314 pin9.

Page 28
Image 28
Acer MB243WABNS service manual Troubleshooting Checking the resolution change IC movement