4. TROUBLE SHOOTING
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4.13 Main LCD trouble
Main LCD control signals are generated by OMAP4430. Those signal’s path are :
OMAP4430 -> LCD Module
Press PWR key turn the power On
Is the circuit powered?
Yes
END
Follow the Power ON
trouble shooting
No
LCD display OK?
START
No
Check LCD Power
1. VCC_LCD_2.8V(C905)-TP1
2. IOVCC_LCD_1.8V(C910)-TP2
3. LCD BL Boost output LED_A(C906)-TP3
Check EMI Fiter
1. Damage Check
2. Signal Check
(TP4)
No
No
No
Change the Main board
Disconnect and reconnect
LCD connector(CN900)
Change LCD module
The LCD works
Yes
Yes
CN900 : LCD connector
EMI Fiter FL701, FL902
U902 :LCD Backlight Driver IC