HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

[Jmine]

Here I am with yet another dead motherboard on my hands, seeking your help guys!

The Charging LED is on and no shorts on the board,19V and 3VPCU are present. I measured the power IC, it goes like this.

VCC: 19.7V
ACPRES: 2.9- 3.0V noticed when measuring this pin the Charging light Blinks
ACDRV: 24V
ACDET: 2.5V When measuring here, the Charging LED turns off
REGN: 6.1V
BQLODRV: 0V
BQHIGHDRV: 2.5V
BQPHASE: 2.5V

I guess these values are good, I went on to measure some voltages on EC.

VCC: 3.3v
AVCC: 3.3V
ACIN: 2.8V
LIDEC: 2.8V
ECPOWEROK: 0V,

I learned that the last one should be higher in order to power on the laptop. What Could be the reason? Help me Diagnose Guys!

You may Find Schematic Here,

https://www.badcaps.net/forum/showthread.php?t=73190

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

I measured the coils,

PL11: 130K
PL17: 8 ohms
PL21: 17ohms
PL22: 63 ohms
PL24: 87 ohms
PL25: 51K
PL26: 500 ohms
PL29: 14K

[mon2]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

So the EC is reporting the power is NOT OK.

Be sure that you are using the proper rated and original power adapter suitable for this logic board.

Measure the voltage to ground of the AD_ID pin athe DCin connector.

This analog voltage is being used to detect if the adapter is suitable or not.

What is the voltage to ground of +3VPCU?

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Measure the voltage to ground of the AD_ID pin athe DCin connector.

What is the voltage to ground of +3VPCU?

AD_ID 0.5v
+3vpcu 3.3V

It's an hp 45W charger

[mon2]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

What is the voltage to ground of +3VPCU_EC?

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

What is the voltage to ground of +3VPCU_EC?

3.3V present @67th pin of EC

[mon2]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Confirm the voltage to ground on each pin of R555.

D18 is acting like a low cost dual input AND gate.

The power good will be high by use of R555 only if BOTH inputs to the diode are good or floating.

If either input pin is LOW because the power is not good or missing a pull-up voltage then this dual diode will be pulled low.

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Confirm the voltage to ground on each pin of R555.

D18 is acting like a low cost dual input AND gate.

The power good will be high by use of R555 only if BOTH inputs to the diode are good or floating.

If either input pin is LOW because the power is not good or missing a pull-up voltage then this dual diode will be pulled low.

R555 I've got nothing on both pins

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Why do I see variable voltage on pin 2 of D18( 2.9v to 3.7v)? It shouldn't be high as cpu section is not yet on?

[mon2]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

So 3VS5 is missing on R155.

Review PU16.

What is the voltage to ground of pin #1 (SY8208BEN / EN1) ?

Voltage of S5_ON signal?

Remove all power. Measure the resistance to ground of PL29 (3VS5).

Post each measurement.

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

So 3VS5 is missing on R155.

Review PU16.

What is the voltage to ground of pin #1 (SY8208BEN / EN1) ?

Voltage of S5_ON signal?

Remove all power. Measure the resistance to ground of PL29 (3VS5).

Post each measurement.

Pu16 pin 1 voltage to the ground: 0v
S5_on pin101 of EC: 0v

PL29 resistance to the ground: 14k

[mon2]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Wait on other comments but your EC maybe with corrupt firmware or defective.

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Wait on other comments but your EC maybe with corrupt firmware or defective.

Thank you very much for the help mon2.!

Got a dumb question though. Do the 3v and 5v supplies turn on before pressing the power button on this board? Is that why they are named 3vs5 and 5vs5? I have no idea of the power sequence of this board.

[mon2]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Yes, these are indicators of different power states.

These enable signals are driven by the EC controller which is a stand alone microcontroller (8051 type) that has its own firmware.

Reference reading:

https://medium.com/@eileenchu/system...s-bf90b4c1b04f

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Yes, these are indicators of different power states.

These enable signals are driven by the EC controller which is a stand alone microcontroller (8051 type) that has its own firmware.

Reference reading:

https://medium.com/@eileenchu/system...s-bf90b4c1b04f

Thank you for the valuable article

[mcplslg123]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Without ECPWROK being present, no point looking for S5_ON.

I'll suggest to check all the requirements of kbc.

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Without ECPWROK being present, no point looking for S5_ON.

I'll suggest to check all the requirements of kbc.

What Should I specifically check, apart from what I've already measured?

[mcplslg123]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Measure Pin14/19/90/93/95/127/124/102/37 of KBC

[Jmine]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

Measure Pin14/19/90/93/95/127/124/102/37 of KBC

14, 19 90 93 95 nothing!
127: 3.1v
124: 3.3V
102: 2.5V
37: 3.3v

[reformatt]

Re: HP Pavilion 15 -- DAY23AMB6C0 REV C, Dead

What about KBC_RST# on pin 13? I'd be checking these things after power is first applied too (after 3920_RST# goes high). EC might detect a fault condition and shut down for example. Failing that, I'd be re-programming the EC as @mon2 suggested with a SVOD or similar.