8.2 Trouble Shooting
8.2.1 Main Board
1.NO SCREEN APPEAR
Measured U401 pin 2 = 2.5 V?
Measured U402 LT1117 pin 2= 3.3V?
Measured CN402 pin 1/2 = 5V?
Yes, all DC level exist
Disconnected the Signal cable( Loose the
Signal cable ),Is the screen show "Cable Not
No, nothing is show
Connected the Signal cable again,
Check LED status.
Led Green
Check the Wire-Harness from CN301
Check Panel-Power Circuit Block
OK,Panel Power OK
Check U203 Data-output Block
OK, U203 data OK
Replace Power board and Check
Inverter control relative circuit
Re-do White balance adjust
Note: 1. if Replace "MAIN-BOARD" , Please re-do "DDC-content" programmed & "WHITE-Balance".
2. if Replace "Power Board" only, Please re-do " WHITE-Balance"
Led Orange
OK, Keyboard no stuck
Measured RGB (R136,R138,R140) H,V Input
at U106 pin 4,10 ,was there have signal ?
Measured ED101~ED108 (GM5120 only)
OK,Wire tight enough
Check digital signal from CN101
Check Correspondent component.
Is there any shortage or cold solder?
Yes.there have OSD show
Connected the Signal cable again,
Check LED status.
Check Power switch is in Power-on
status , and check if Power switch had
been stuck ?
OK,input Normal
Measured Crystal X201(14.318MHz)
OK,clock
Replace U203 (GM5120/2120)
OK
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IBM L170 Service Manual
Led Green
Replace U202
Flash Rom
Led orange
Check Correspondent
component short/open
NG
( Protection Diode )