LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. TROUBLE SHOOTING
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4.11 Keypad backlight trouble
Key Pad Back Light is on as below :
Key pressing
→
PM6658 KYPD_LED_EN go to Low
→
LED On (Key Pad LED controlled by PM6658)
Start
Check device sh ort :
LD700~705 and R714~719 (Main)
NO
Yes
Key press
Signal KYPD_LED_EN
is Lo w?
+VPWR is OK?
Change the main board
NO
Yes
Yes
Check device open :
LD700~705 and R714~719 (Main)
NO
Some LED
is not work?
Work well?
Yes
Change the main board
NO
End
LD700~705 (Main)
LD702 (+VPWR)
VA711 (KYPD_LED_EN)
R714
R7
19
R7
15
R7
17
R716
R718