Acer RB23WABAS service manual Circuit section

5. Troubleshooting (continued)

5.2 Nothing display on screen (screen is black, color of LED is blue)continued

ACER H233H 25

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Check the 5V power supply for

P301 pin 4,5,6.

NG

Check the I304 pin2 if voltage is 3.3V

OK

Check the I305 pin2 if voltage is 1.2V

OK

NG

NG

Proceed "Checking the DC/DC converter

circuit" section.

Proceed "Checking the DC/DC converter

circuit" section.

	Check the I301 pin2 if			Failure Point
			NG
OK	voltage is 5V			1) FB301 is open..
		OK
	Check if the voltage
	between I301 pin2 and
	pin3 is above -0.7V

OK

Failure Point

I301 is failure.

Check the input voltage level whether was changed when

pressed function keys on the P309 pin1

				NG
					Check if the voltage on I308 pin 108 that is
						from 3.3V to 0V.
	OK
								NG
							OK
Check the P307 all LVDS signals.					Failure Point
					I308 is failure
			Failure Point
			1) Printed wire broke between P307 and
		NG
			I308 LVDS signals.
	OK
			2) I308 is failure.

Failure Point

1)The LVDS cable broke between P307 and LCD module.

2)LCD module is failure.

Failure Point

1)Printed wire broke between P309 pin 1 and I308 pin 108.