Lenovo Y530 power button only works with battery

[unimatrix93]

So my Lenovo Y530 power button (and power LED) only works with battery. If I only plug in the AC, the power doesn't flash and nothing happens if press it.

20V present on the main power rail with the AC plugged in.

Also worth mentioning:
If I inject 19V/1A on the + pin of the AC IN, nothing happens current draw is 0.016A V is 19V. But If Inject the same power trough a CAP after the first MOSFETS the board starts up (power LED flashing) and the current draw is 480mA.

[mon2]

Re: Lenovo Y530 power button only works with battery

Remove all power. Meter in resistance mode.

Check the resistance of the first 2 mosfets to see if they are defective.

Meter in resistance mode (2k scale is ok).

Check each mosfet with meter probes across:

Source (1-2-3) & Drain (5-6-7-8)
Source (1-2-3) & gate (4)
Gate (4) & drain (5-6-7-8)

Post each measurement. Repeat for the 2nd mosfet. Checking for a low resistance = defective mosfet.

Also post the markings of each mosfet so we can find their datasheets (or a valid replacement).

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

Remove all power. Meter in resistance mode.

Check the resistance of the first 2 mosfets to see if they are defective.

Meter in resistance mode (2k scale is ok).

Check each mosfet with meter probes across:

Source (1-2-3) & Drain (5-6-7-8)
Source (1-2-3) & gate (4)
Gate (4) & drain (5-6-7-8)

Post each measurement. Repeat for the 2nd mosfet. Checking for a low resistance = defective mosfet.

Also post the markings of each mosfet so we can find their datasheets (or a valid replacement).

Meter in 2k resistance mode.

MOSFET1 AON6366E_DFN8-5:
Every combination is OL.

MOSFET2 AON6414AL_DFN8-5:
Same values.

Also, If I inject the power on the drain side of MOSFET 2 the power led flashes, the system wants to start up. 20V/480mA load.

[mon2]

Re: Lenovo Y530 power button only works with battery

Review the voltages on the mosfet.

What are the mosfet markings?

Can you post or link the schematic for your logic board so we are referencing the same?

Which charger IC is onboard?

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

Review the voltages on the mosfet.

What are the mosfet markings?

Can you post or link the schematic for your logic board so we are referencing the same?

Which charger IC is onboard?

With AC in:
PQ201 6366E GA0F14
20.7V on D
20.7V on S
26.5V on G

PQ202 6414A GA3Y58
20.7V on S
26.5 on G
20.7 on D

Schematic:
https://1drv.ms/b/s!Ar4hHP2toEdogtU4...bmXWA?e=n0OToz

[mon2]

Re: Lenovo Y530 power button only works with battery

Mosfet voltage looks ok.

Are you using the original laptop power supply for testing ?

There is an ADAPTER_ID that must be present for this to work properly.

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

Mosfet voltage looks ok.

Are you using the original laptop power supply for testing ?

There is an ADAPTER_ID that must be present for this to work properly.

Yes I do.

ADAPTER_ID is not present (0v) as far as I see.

[Vesko356]

Re: Lenovo Y530 power button only works with battery

Try with known good Lenovo power supply.
Measure resistance to ground (the adapter must be disconnected from the mains and the laptop itself) between the Id pin and the ground (at the jack) of your current power brick.

[ktmmotocross]

Re: Lenovo Y530 power button only works with battery

replace first mosfet

[Vesko356]

Re: Lenovo Y530 power button only works with battery

replace first mosfet

Agree, it is also a logical reason for the behavior of the machine as described, although the data from their measured voltages and resistances seem to be OK.

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

Try with known good Lenovo power supply.
Measure resistance to ground (the adapter must be disconnected from the mains and the laptop itself) between the Id pin and the ground (at the jack) of your current power brick.

I measure 0.996 kOhm resistance to ground between the ID pin and ground.

DMM is set to 2k.

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

Agree, it is also a logical reason for the behavior of the machine as described, although the data from their measured voltages and resistances seem to be OK.

When I first tried to diagnose the laptop, I suspected the SuperIO chip because of the unresponsive power button.

But when I tried with the battery the button worked, also the laptop does try to start up when I inject power at the second mosfets drain or on one of the caps of the main power rail.

[mon2]

Re: Lenovo Y530 power button only works with battery

With no power, check the resistance across the battery mosfet pins.

[Vesko356]

Re: Lenovo Y530 power button only works with battery

I measure 0.996 kOhm resistance to ground between the ID pin and ground.

DMM is set to 2k.

Seem ok, it's a 135W power brick right?

Replace the mosfet as ktmmotocross suggested.

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

With no power, check the resistance across the battery mosfet pins.

Measurements across PQ203 mosfet:
Every combination is OL.

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

Seem ok, it's a 135W power brick right?

Replace the mosfet as ktmmotocross suggested.

So I replaced the first MOSFET now 20V is not passing trough it.

I have 0V on both gate and source if I apply power on the ACIN pin.

Its the original 135W power brick and its supplies 20V, I checked it.

[Vesko356]

Re: Lenovo Y530 power button only works with battery

So I replaced the first MOSFET now 20V is not passing trough it.

With what exactly? What are the markings of the new mosfet?
Are you sure you've soldered it properly (not upside down for example)?

I have 0V on both gate and source if I apply power on the ACIN pin.

Are you playing there with the bench power supply? If yes, be very very careful , because if you accidentally touch the ADAPTER_ID line with the positive (+20v) probe, you can say goodbye to SIO chip, you have been warned.
Try with the original adapter. (because ADAPTER_ID must be present)

Yes I do.

ADAPTER_ID is not present (0v) as far as I see.

ADAPTER_ID is not a (positive) voltage line! It's a signal line, SIO chip receive this signal as a value of the resistance to the ground in it.
That's why I asked above to measure this value at the jack of your current power brick.

[Vesko356]

Re: Lenovo Y530 power button only works with battery

Measurements across PQ203 mosfet:
Every combination is OL.

Be more specific - do you measure resistance in Ohms between S/D/G to ground, or between the S/D/G pins of the battfet itself in diode mode???

[unimatrix93]

Re: Lenovo Y530 power button only works with battery

With what exactly? What are the markings of the new mosfet?
Are you sure you've soldered it properly (not upside down for example)?

I'm pretty sure I soldered it properly, also here are the markings on the mosfets:

MOSFET1: 6366E, GA0F14
NOSFET2: 6414A, GA8U2K

Are you playing there with the bench power supply? If yes, be very very careful , because if you accidentally touch the ADAPTER_ID line with the positive (+20v) probe, you can say goodbye to SIO chip, you have been warned.
Try with the original adapter. (because ADAPTER_ID must be present)

Sure, I pay attention to it.


ADAPTER_ID is not a (positive) voltage line! It's a signal line, SIO chip receive this signal as a value of the resistance to the ground in it.
That's why I asked above to measure this value at the jack of your current power brick.

0.996 kOhm at the jack of the power brick and 0.005 kOhm on the ADAPTER_ID pin on the board to ground.

Be more specific - do you measure resistance in Ohms between S/D/G to ground, or between the S/D/G pins of the battfet itself in diode mode???

Sorry, I meant it in resistance mode between S/D/G to ground and between S/D/G. In diode mode:
S to D: 0.542
D to S: 2.431
G to S: 1.814
G to D: 2.476

Also, I found a short to ground on the 3VALW line. If I apply 2V/4A on it the PCH chip is getting slightly warm, but nothing else.

[Vesko356]

Re: Lenovo Y530 power button only works with battery

0.996 kOhm at the jack of the power brick and 0.005 kOhm on the ADAPTER_ID pin on the board to ground.



Sorry, I meant it in resistance mode between S/D/G to ground and between S/D/G. In diode mode:
S to D: 0.542
D to S: 2.431
G to S: 1.814
G to D: 2.476

Also, I found a short to ground on the 3VALW line. If I apply 2V/4A on it the PCH chip is getting slightly warm, but nothing else.

0.005 kOhm is 5 Ohm - this is almost short, along with the shorted PCH means that this machine is now beyond economical repair.
Playing with a bench power supply on the motherboard without the theoretical and/or practical skills and understanding on a subject does not lead to anything good as a result.