LG VX5400 Service Manual page 93

Check battery voltage > 3 ..4V
Push power- on key and
check the level change of U 500
Check the voltage of
the following port at U 500
+ 1 . 86V _MSMC
+2.6V_MSMP
+2.6V_MSMA
+2.8V_TCXO
Logic level at PS _ HOLD ( R516 )
of U500=High ?
Does it work properly ?
The Phone will power on
Copyright@2007 LG Electronics. Inc. All right reserved.
Only for training and serving purposes
START
YES
PWR_ON
YES
YES
YES
NO
YES
Re-download software
and try again
Checking Flow
Checking Flow
Charge of Change Battery and try again
NO
Check the contact of power - key
NO
Replace U500
NO
Re-download software
and try again
NO
Does it work properly ?
-93-
YES
NO
Re-download software
and try again
LGE Internal Use Only