Device Peripheral Trouble Shooting (Mmi Testing); Lcd Display Test - Asus P552W Manual

time),current is still not raising up.
E. Measure the voltage described above from A~E, according to the
experience the voltage level on PWR_EN and SYS_EN would be
abnormal(about 1.~ V)。
If above items have been done, and the system still can't power on.
Please discharge the super cap(CE901).Use the tweezers to discharge
the supercap to ground until the voltage level on super cap down to
0.4V
Summary:
Measurement Check list for device unable to power on:
a) VCC_BBAT
b) nHWRST_OUT_R
c) nBATT_LOW
d) 32KHz(TXTAL_IN)
e) SYS_EN
f) VCC_MVT
g) SYS_EN Power Group
(VCC_MVT;VBUCK3;VCC_MVT_PLL_CORE;VCC_MVT_CLK;LDO2；
LDO3)
h) PWR_EN
i) PWR_SDA,PWR_SCL
j) V_APP;V_COMM
k) 26MHz
l) OneNAND_nCS
m) SD0
2.3 Device Peripheral Trouble Shooting
(MMI Testing)

2.3.1 LCD Display Test

This test item is for LCM interface and backlight, if this item NG,
please check the following signal:
A. LCD_PWR_EN should be 1.8V
B. VCC_18V should be 1.8V
C. VCC_2.8V should be 2.8V
D. LCD_nRESET should be 2.9V
華 碩 電 腦
華 碩 電 腦
GTC ■ Service Manual
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