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4 Troubleshooting

4 Troubleshooting
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4-1 No Power(LS15HAA/LS15HAB)
Yes When Pin 4 of CN600 is 0V does proper DC 13V, 5V appear at Pin 1, 2 and 6, 7 of CN600 separately? Yes When Pin 3 of IC602 is DC 5V does proper DC 3.3V appear at Pin 2 of IC602? Yes When pin1 of IC600 is DC 5V does proper DC3.3V appear at Pin3 of IC600? Yes Replace AD Board. No No No '

Change IP Board.

Check IC602 and related circuit.

Check IC600 and related circuit.

4-1

4 Troubleshooting

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4-2 No Power(LS17HAA/LS17HAB/LS17HAT/LS19HAA/LS19HAT)
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Yes * When Pin 4 of CN600 is 0V does proper DC 13V, 5V appear at Pin 1, 2 and 6, 7 of CN600 separately? Yes No

Change IP Board.

When Pin 4 of IC600 is DC 0.5V does proper DC 0.5V appear at Pin 5 and 6 of IC600? Yes When Pin 2, 3 of IC601 is DC 3.3V does proper DC 4.3V appear at Pin 1 of IC601? Yes When Pin 2, 3 of IC601 is DC 4.3V does proper DC 2.5V appear at Pin 4 of IC601?

No

Check IC600 and related circuit.

No

Check IC601 and related circuit.

No

Check IC601 and related circuit.

* 0V means power on state. When the monitor work well except DPMS and power switch off, 0V should be applied to number 4 of CN600.

4-2

4 Troubleshooting

4-3 No Video (ANALOG)
Check signal cable connection and power.

1

X400 oscillate properly?

No

Replace or check related circuit.

Yes Is there R, G, B input at R101, R103 and R105? Yes Is there Hsync, Vsync waveform
2 3

No

Check input part.

No

Check IC400 and related circuit.

at Pin 100, 1 of IC 400? Yes Is there Hsync, Vsync waveform
2 3

No

Check IC200 and related circuit.

at Pin 41, 42 of IC 200? Yes Does the output signal appear at Pin 17~20, 22~27 of CN400? Yes There are DC 5V at Pin 1, 2 and 3 of CN400? Yes Replace LCD Panel. No Check PANEL_EN SIGNAL at R236 is High(On:High) and BL_EN signal at R605(ON:Low) is Low No

Check IC400 and related circuit.

4-3

4 Troubleshooting

WAVEFORMS 1 2

3

16V 100nF C402

C414 100nF 16V MO
XREF

+3.3V_MAIN

C416 18pF 50V NULL MO
24.0MHz

SCALER_RESET
X400

AD0 AD3

XREF XREF XREF

NULL MO

C418 18pF 50V

RGND

4C-49/SM5H,24MHZ,16PF

+3.3V_MAIN

2 3

AVDD_DVI

VSYNC0 GND

1

81 BUSTYPE 82 NC 83 NC 84 NC 85 NC 86 VDDC 87 GND 88 GND 89 VDDP 90 NC 91 NC 92 AD0 93 AD3 94 HWRESET 95 XIN 96 XOUT 97 AVDD_MPLL 98 GND 99 HSYNC0 100

BYPASS

R+

G+

G-

C423 100nF 16V

C417 100nF 16V MO

C415 100nF 16V

4-4

1 2 3 4 5 6 7 8 9 10 11

B+ B-

LVB2P LVBCKM

LVB0P

LVB1M

GND LVB0M

LVB2M

C403 100nF 16V

C405 100nF 16V

C406 100nF 16V

C404 100nF 16V

LVB1P

GND VDDP

80 79 78 77 76 75 74 73 72 71 70

4 Troubleshooting

4-4 No Video (DIGITAL)
Check signal cable connection and power.

1

X400 oscillate properly?

No

Replace or check related circuit.

Yes Is there R, G, B input at
4 5 6

No

Check input part.

R110, R112, R114, R111, R113 and R115? Yes Is there waveform
7

No

Check input part.

at R11, R117? Yes Does the output signal appear at Pin 17~20, 22~27 of CN400? Yes There are DC 5V at Pin 1, 2 and 3 of CN400? Yes Replace LCD Panel. No Check the panel EN signal at R222 and BLEL signal at R603. No

Check IC400 and related circuit.

4-5

4 Troubleshooting

WAVEFORMS 1 2

3

4

5

6

7

4-6

MAIN

C108 100nF 16V

C124

330nF 16V

B
2 1 2 1 2 1 2 1 2 1 2 1 2 1 2

A B B B B A B B B A

A

A

A

A

C C C
3 3

C C
3

C D105 D103
3 3

C

C

D106

D107

D114 MMBD4148SE

D113 MMBD4148SE

D100 MMBD4148SE

MMBD4148SE

MMBD4148SE

MMBD4148SE

MMBD4148SE

D109
3 3 XREF XREF XREF XREF XREF XREF XREF XREF

3

4 5 6 7

R116 R117 R118 R119 R120 R121 R122 R123

22ohm 22ohm 22ohm 22ohm 22ohm 22ohm 22ohm 22ohm

1/10W 1/10W 1/10W 1/10W 1/10W 1/10W 1/10W 1/10W

RX2RX1RX0RX2+ RX1+ RX0+ RXC+ RXC-

XREF

SCL_DDC_D
XREF XREF

SDA_DDC_D CHK_DVI

+5V_DDC_D

C3 4 A2 5 C4 6 1 C1 2 A1 3

R125 1K 1/16W
C2

ZD102 MMQA5V6T3

HSYNC_IN_A VSYNC_IN_A

XREF

XREF

XREF

RX2+ RX2RX1+ RX1-

XREF

XREF XREF

+5V_DDC_D

XREF

RX0+ RX0UDZS5.6B-T ZD1 2 B RXC+ RXC

XREF

XREF XREF

4 Troubleshooting

4-7

4 Troubleshooting

Memo

4-8