Dell XPS 9300 13” motherboard FDQ30 LA-H811P rev 1.0 works with battery only

This laptop doesn’t charge the battery with his PSU 65W USB C and doesn’t power on with PSU connected
No shorted components or damaged

Hello!

Connect the power supply to the board via a USB Type-C power meter and specify the voltage and current displayed on the meter.
(picture source: ubuy.com):

20V
0,005A

Measure the voltages to ground on any pin of resistors PR200, PR211 with the power supply connected only (without the battery).

If you mean pin 1-4
PR200 = 20V
PR 211= 0,1V

Measure the voltages to ground on pins 1, 4, 8, 12, 14, 15, 16, 17, 18, 19, 21, 22, 24, 25 of charger chip PU200 with the power supply connected only (without the battery).

1= 0,1V
4=0,8V
8= 1V
12=0V
14=20V
15=20V
16=20V
17=0,5V
18=1V
19=3,68V
21=0,35V
22=0,35V
24=0V
25=0V

Sorry after measuring voltages I checked other components and I found the resistor and diode damaged
I’m going to replace them




After replacing resistor and diode damaged PD 201 blows again.

PD201 pin 2= 20V (blowed)
PD202 pin 2= 0V
PR208 pin 2= 250 ohm (maybe to low)?
PR208 pin 1= 10 M ohm

Ok
PC227 was damaged
After replacing I got 20V on PR208 and also on pin 17 of PU 200
But notebook doesn’t power on now even with battery only

Remeasure the voltages suggested in post #6 and also remeasure the voltage to ground on any pin of resistor PR211 with the power supply connected only.

PR211= 8,3V

1=8,3V
4=7,3V
8=5V
12=0V
14=20V
15=20V
16=20V
17=19,3V
18=5,1V
19=3,68V
21=0V
22=0V
24=0V
25=0V

I checked again PU200 and now some voltages have changed value.

Like PR211=1,6V

1=8,3V
4=8,7V
8=5,1V
12=8,6V LAST MEASURE
14=20V
15=20V
16=18,7V
17=19,6V
18=5,1V
19=3,8V
21=2V
22=2V
24=2,9V
25=0V

Now you have given two different measurements. Which ones are correct???

Now the correct measurement is the last one.
Situation has changed when I measured the the last pin and to confirm all voltages I checked it again from 1 pin and I noticed different measures

Measure the resistances to ground on pins 8, 18 of charger chip PU200.
If both resistances are high (in the kΩ range or greater), replace the chip PU200.

I replaced PU 200 no power on but I got a new measurement.
You can see the message #11
I changed old measure with last correct voltages and are marked as “LAST MEASURE”

I have something wrong:
PL 401 = 3,3V should be 5V
PL 250 = 3,66V
PL 702 = 0V

I removed PL 401 and on PU400 side I have 5V so there is something wrong on other side.

Check the resistor PR206 (2Ω).

valieromarco ha scritto:I have something wrong:
PL 401 = 3,3V should be 5V

This is more than obvious, as the main power rail "B+" voltage is way too low:

valieromarco ha scritto:Like PR211=1,6V

Sorry PR 211 I forgot to change right measure 8,3V

PR206 was damaged (70 ohm) now voltage 20V both pin
But still remains 3,3V on PL401

Measure the voltages to ground on pins 1, 3, 10, 12, 13, 15 of chip PU400 with the coil PL401 installed.

1=8,3V
3=3,53V
10=6,5V
12=0V
13=1,21V
15=3V

Open the jumper PJP400 and remeasure the voltage to ground on coil PL401.