ASUS UX435E - zwarcie na płycie głównej

Płyta główna UX435EG zwarcie do GND miał podwójny tranzystor PQH8901 po wymianie zwarcie ustało po podłączeniu ładowarki nie przełącza na 20V cały czas jest 5V 20mA na obu gniazdach tak samo. Jakieś wskazówki naprawy?

Hello!

- Please specify the motherboard revision number.
- Measure the voltages directly on the capacitors C3410, C3411.

UX435EG R2.2
C3410- 3.258V
C3411- 1.571V
the same on both USB-C

PRS8901 - 4,6V why?

Set your multimeter to diode test mode and measure the voltage drops to ground on pins 1, 2, 3, 4, 5, 11, 12, 14, 15, 19, 20 of the chips U3403, U3404 with the positive (red) probe connected to ground.

U3403:
1- 0.754V
2- 0.754V
3-0,661V
4-0,753V
5-0,753V
11-0,600V
12-0,606V
14-0,620V
15-0,620V
19-0,824V
20-0,824V

U3404:
1- 0.753V
2- 0.754V
3-0,662V
4-0,752V
5-0,752V
11-0,599V
12-0,606V
14-0,749V
15-0,749V
19-0,825V
20-0,825V

- Measure the resistances directly on the capacitors C3401, C3414, C3419.
- Measure the resistance between pin 1 of capacitor C3401 and pin 1 of capacitor C3414.
- Measure the resistance between pin 1 of capacitor C3424 and pin 1 of capacitor C3414.

C3401 - 5,4k Ω
C3414 - 930 Ω reverse probe 840 Ω
C3419 - 5,4k Ω

resistance between pin 1 of capacitor C3401 and pin 1 of capacitor C3414 is 10k Ω and rise to 80k Ω
resistance between pin 1 of capacitor C3424 and pin 1 of capacitor C3414 is 930 Ω reverse probe 830 Ω

Still need help

daro19862 написав:resistance between pin 1 of capacitor C3424 and pin 1 of capacitor C3414 is 930 Ω reverse probe 830 Ω

Sorry, my mistake.
I meant pin 1 of C3414 and pin 1 of C3419, so also please measure this resistance.

However, pin 1 of C3424 is directly connected to the pin 1 of C3414, so this resistance should be close to 0Ω, but you measured around 1kΩ. Please, check your meter.

Pin 1 of C3414 and pin 1 of C3419 is 80k Ω
pin 1 of C3424 and pin 1 of C3414, have 0Ω (I made a mistake earlier)

Matic, Do you have any other ideas?

Replace the USB Type-C power supply controller chip U3406.

After replace U3406 nothing change

Remeasure the voltages directly on the capacitors C3410, C3411.

C3410- 3,260V
C3411- 1,604V

Remove the chips U3403, U3404 from the board and measure the voltage drops to ground on the pads 11, 12 at the place of these two chips with the positive (red) probe connected to ground.

U3403:
11-0,590V
12-0,600V
U3404:
11-0,600V
12-0,610V

Check the following continuities:
- Between pin A5 of the Type-C port J3401 and pin 1 of capacitor C3454.
- Between pin B5 of the Type-C port J3401 and pin 1 of capacitor C3455.
- Between pin A5 of the Type-C port J3402 and pin 1 of capacitor C3456.
- Between pin B5 of the Type-C port J3402 and pin 1 of capacitor C3457.

It's best to use a USB Type-C test card:

I dont have C3454,C3455,C3456,C3457 mistake or you have different BV ?

I have this:


Pin 5,6 IC U3404 is connected to B5 J3402 and goes through the connector to test card pin name "VCC" (the description on test card is probably not correct)
Pin 4,7 IC U3404 is connected to test card pin name "D-" (the description on test card is probably not correct) I can't check the socket J3402 because I don't have access to the "Ax" pins.

Pin 5,6 IC U3403 is connected to B5 J3401 and goes through the connector to test card pin name "VCC" (the description on test card is probably not correct)
Pin 4,7 IC U3403 is connected to test card pin name "D-" (the description on test card is probably not correct) I can't check the socket J3401 because I don't have access to the "Ax" pins.

daro19862 написав:I dont have C3454,C3455,C3456,C3457 mistake or you have different BV ?

That's strange.
I'm useing the BoardView UX435EG Rev: 2.2 From this post and there are all these capacitors. Which BoardView are you using exactly?

daro19862 написав:(the description on test card is probably not correct)

The pin descriptions on your test card seems fine to me.