Dell Inspiron 15 3000 Series not turn on

Model : Dell Inspiron 15 3000 Series
Board id : Cedar-Intel-MB 13269-1 PWB FX3MC Rev A00

Laptop can't switch on. When press power key, power comsumption on DC Power Supply show about 0.028 amp and stop. No cpu fan spin. Need help.

PL4501 - 5V
PL4502 - 3.3V
Q2402 Drain and Source - 3.3V, Gate - 0V
Q2403 Drain - 3.3V, Gate and Source - 0V
LIDSW pin 2 and 3 - 3.3V , pin 1 - 0V
KBC pin 15 (RSMRST) - 3.3V
ECRST# - 3.28V
RN1901 RTCRST and SRTCRST - 3.3V

Measure the voltages on pins 1, 5, 6, 8, 12, 15, 16, 17, 20 PU4901.

PU4901
Pin 1 -0V
Pin 5 - 0.68V
Pin 6 - 1.79V
Pin 8 - 1.34V
Pin 12 - 5.2V
Pin 15 - 6.56V
Pin 16 - 3.37V
Pin 17 - 0V
Pin 20 - 1.36V

Did you take the voltage measurements after pressing the start button?
Measure the voltages of PL4902.
Measure voltage and resistance to ground on all coils.

No. But for now when connect adapter or dc power supply, laptop automatically open. Power comsumption on dc power supply is around 0.025 amp and 0.033 amp. Not stable.

PL4902 - 1.35V
PL4801 - 1V
PL4501 - 5.2V
PL4502 - 3.37V
PL4401 - 2.65V (Without Battery)
PL4701 - 0V ( Resistance to Ground - 109 Ohm )

U3601 pin 1,2,4 - 5.2V / pin 6,7 - 3.37V / pin 3,5 - 3.3V
but pin 8,9 only have 1.39V and pin 13,14 only have 0.6V
Resistance to ground on pin 8,9 - 10.3K
Resistance to ground on pin 13,14 - 3M

Replace U3601 = G5016KD1U

U3601 is ok. I already tried to replce it with about 2 ICs. But problem still exit.

Measure the resistances and voltages to ground on pins 10, 12 of chip U3601.

I think U3601 is not properly solder. So i resolder it. For now, when press power key, DC power supply show power comsumption about 0.219 amp for a while and then stop.

(When press power key for a while)
U3601 pin 10 and 12 is about 8V. Resistance to ground on pin 10 and 12 is 0L.
Pin 8 - 3.3V
Pin 13 - 5V
PL4902 - 1.3V
PL4801 - 1V
PL4701 - 1.7V

Measure the following voltages to ground for a short time, when the machine is turned on (power consumption is 0.219A):
- On pin 5 of chip PU5101.
- On pins 7, 84, 107 of KBC chip.

Pin 5 of chip PU5101 - about 1.35V
KBC pin 7 - about 2.5V
KBC pin 84 - without press power key 1.5V, after pressing power key about 2.5V
KBC pin 107 - about 3V

Also measure the voltages to ground on pins 1, 3 of chip PU5101 under the same conditions.

PU5101 pin 1 is 3.37V (with or without press power key)
PU5101 pin 3 is about 3.2V (with press power key)

Measure the resistance to ground on pin 5 of chip PU5101.

PU5101 pin 5 is 40K.

Open (cut) the jumper PG5105 and remeasure the voltage to ground on pin 5 of chip PU5101.

Open (cut) the jumper PG5105 and voltage to ground on pin 5 of chip PU5101 is about 1.35V when press power key.

Replace the chip PU5101 (TLV70215DBVR).

Replace the chip PU5101 and now laptop is power on but no display. All coils have voltages.
PL4501 - 5V
PL4502 - 3.3V
PL4902 - 1.35V
PL4801 - 1V
PL4701 - 1.8V

Measure the voltages on pins 1, 4, 8, 20, 21 of LCD1.