ASUS T500 MB Service Manual
5
2. Cannot power on
Solution:
1
Check if the battery connector and its soldering are oxidized or damaged
2
Check if the following voltage, and GND has short circuit or abnormal voltage
VBAT 3.8--4.2V
VCORE 0.7--1.4V
VSYS 1.825/2.2V
VPA 0.5-3.4V
VTXCO 2.8V
VA 2.8V
VCAMA 2.8V
VCN28 2.8V
VCAMA 2.8V
VUSB 3.3V
VEMC_3V3 3.3V
3
Check if start-up circuit is abnormal
4
If the start-up circuit is about 20 MA, check if the soldering of crystal oscillator circuit is normal
5
For those start-up current abnormally above 1A, check if VBAT circuit is shorted to ground, investigate each
locations
’
grounding diodes and other key components
6
For those start-up current abnormally around 100MA, touch if there is any heating part on MB and focus on
their investigation
7
X-ray: check each main chip
’
s soldering, CPU/Flash/PMIC(MSM8916/PM8916)
8
Add soldering or re-solder each main chip and confirm again
9
Replace CPU/Flash/PMIC
CPU MSM8912
Flash
PMIC
PM8916
Battery connector