MiTAC 8355 service manual No Display, Parts Signals

8355 N/B MAINTENANCE

8.3 No Display (System Failure)

No Display

Board-level

	NO	Replace
LCD module		LCD.
OK?
	Yes

Make sure that CPU module,

DIMM memory are installed

Properly.

Display		Yes
			Correct it.
OK?
	No
1.Try another known good CPU
module, DIMM module and BIOS.
2.Remove all of I/O device (HDD,
CD-ROM…….) from
motherboard except LCD

Replace

Motherboard

Troubleshooting

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.

System ClockReset Signal

Parts:		Signals:	Parts:	Signals:
U9	R96	+3V	SW2	PWRBTN#
C191	R97	CPUCK+	U11	H8_RESET#
C189	R785	CPUCK-	U13	SB_PWRBTN#
R531	X1	GCLK_NB	U507	RSMRST#
R92	C182	66M_AGP	U510	ALL_PWROK_5V
R94	C212	SMB_DATA1	U511	ALL_PWROK_2.5V
R284	R72	SMB_CLK1	U513	MAIN_PWROK
R536	R77	USB_CLK	X5	PG_1.2V
R78	R87	SB_VCLK	X501	PG_VCC_CORE
R91	R89	PCI_SB_CLK	Q15	PCIRST#

Display

OK?

Yes

1.Replace faulty part.

2.Connect the I/O device to the M/B one at a time to find out which part is causing the problem.

R73	R82	14M_SB_IOSC	Q533	CARD_RESET#
R646	R183	CODEC_XIN	Q534	PCI_1394_RESET#
R90	L510	PCI_CARD_CLK	R611	MINIPCI_RESET#
D2		PCI_1394CLK	R617	AGP_RESET#
		CLK_LPC33	R633	HDD_RST#
		MINI_PCI_CLK	R727	CDROM_RST#

No

14M_SB_APICCLK R789 LPC_SPIO_RESET#

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