MiTAC 8355 service manual AGP Controller Failure, Charge BD J2,J3 are cold colder?

8355 N/B MAINTENANCE

8.4 AGP Controller Failure LCD No Display

Symptom:

There is no display on LCD although power-on-self-test is passed.

AGP Controller Failure

1.Confirm LCD panel or monitor is good and check the cable are connected properly.

2.Try another known good monitor or LCD module.

Board-level

Troubleshooting

Check if MB:U506,U16, J2, J3, Yes

Charge BD: J2,J3 are cold colder?

No

Re-soldering.

Display		Yes	Replace faulty
OK?			LCD or monitor.
	No

Remove all the I/O device & cable from motherboard except LCD panel or extended monitor.

Replace

Motherboard

One of the following parts on the mother-board may be defective, use an oscilloscope to check the following signal or replace the parts one at a time and test after each replacement.

Parts:		Signals:
U506	X3	TXCLK+	BLADJ

		Yes	Connect the I/O device & cable
Display			to the M/B one at a time to find
OK?			out which part is causing the
	No		problem.

U511	F501	TXCLK-	ENAVDD
U9	Q518	TX2CLK+
U16	Q503	TX2CLK-
J2	Q501	TXOUT[0:3]+
J3	R503	TXOUT[0:3]-
R94	R504	TX2OUT[0:3]+
C211	L46	TX2OUT[0:3]-
R137	L39	PANEL_ID[0:3]
R141	L42	ENABL_VGA
R139	D503	+PANEL_VDD

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