HP 15-bw065 (LA-E831P) no EC_ON signal

[Xruss]

HP 15-bw065 (LA-E831P) malfunction: no EC_ON signal from the cartridge.

Trouble: the laptop did not turn on, there was no 19v at the output from the keys on the charger.
They replaced transistors PQB11 and PQB12 - 19v appeared.
But now KB9022 cartridge doesn't output EC_ON 3,3v when I pressed the power button on the notebook.

The power supply of the cartridge is normal.
On the legs: 9, 22, 33, 67, 96, 111, 125 - 3,3v
On pins: EC_ON, EC_KBRST#, PM_SLP_S3#, PM_SLP_S5#, PCH_PWROK, SPOK, SYSON, EC_RSMRST#, MAINPWON, SUSP#, VGATE - [b]0v.
On the legs: 0. 95VS_PWR_EN#, EC_TX/GPIO16, SUSP_LED#/GPIO19, EC_RST#, KSI0-7/GPIO30-37, BATT_TEMP, ADP_ID, EC_SMB_CK1, EC_SMB_DA1, WL_PWREN_EC#, USB_ON#, EC_ACIN, LID_SW#, ON/OFFBTN# (when the power button is pressed, the voltage drops to 0v) - 3.3v.
On pins: 66 and 109 (VCIN0_PH) - 2.8v
On pins: 27 - 1.5v
Voltages on unspecified pins are 0v or below 0.3v.

When power supply is connected, voltage 3,3v appears on the EC_ON multiple and in 3 seconds it drops to 0v.
I unsoldered the solder pin and fed 3.3v to the EC_ON bus, then the standby voltages appeared.
I replaced the cartridge with a new one (I flashed it).
Any tips for solving this problem?

Schematic ---> https://www.badcaps.net/forum/showth...44#post1229744

[mon2]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

Hi.

1) You will need to move the above schematic to the schematic forum to keep it organized and so that future readers can find the same.

2) Confirm if the voltage to ground of +3VALW_EC is stable when the unit is ON/OFF.

3) Confirm the voltage to ground on the charger IC (PUB1) of:

REGN (pin # 16) ; should be ~6 volts
ACOK (pin # 5)
ACDRV (pin # 4) ; should be ~25 volts to enable the 2*DCin mosfets
CMSRC (pin # 3)
ACP (pin # 2) ; this and ACN are important to gauge the 'load' of the rail
ACN (pin # 1) ; too large of a voltage drop = too high of a current consumption = turn it OFF

[Xruss]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

Hi.

1) You will need to move the above schematic to the schematic forum to keep it organized and so that future readers can find the same.

2) Confirm if the voltage to ground of +3VALW_EC is stable when the unit is ON/OFF.

3) Confirm the voltage to ground on the charger IC (PUB1) of:

REGN (pin # 16) ; should be ~6 volts
ACOK (pin # 5)
ACDRV (pin # 4) ; should be ~25 volts to enable the 2*DCin mosfets
CMSRC (pin # 3)
ACP (pin # 2) ; this and ACN are important to gauge the 'load' of the rail
ACN (pin # 1) ; too large of a voltage drop = too high of a current consumption = turn it OFF

+3VALW_EC - stable 3.3v

REGN (pin #16) - 6.07v
ACOK (pin #5) - 3.3v
ACDRV (pin #4) - 25v
CMSRC (pin #3) - 19v
ACP (pin # 2) - 19v
ACN (pin # 1) - 19v

[Sephir0th]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

You might dig into the wrong side of the road. I guess it needs healthy +3VALW and +5VALW rails for stable Enables, too

Also with HP laptops a known working charger of correct wattage has to be ruled out.

[mcplslg123]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

Does RSMRST# appears after pressing power button?

[Xruss]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

Does RSMRST# appears after pressing power button?

There is EC_RSMRST# which should appear from 1.8v voltage after starting the PU301 (+3VALWP - +5VALW).

[Xruss]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

You might dig into the wrong side of the road. I guess it needs healthy +3VALW and +5VALW rails for stable Enables, too

Also with HP laptops a known working charger of correct wattage has to be ruled out.

The +3VALW and +5VALW buses are normal, the load is more than 700 ohms. SPOK (PGOOD), +3VALW and +5VALW appear when EC_ON appears briefly on PU301.

[Sephir0th]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

So half of the important informations were hidden till now.

If there are voltages present, even for a brief moment then you need to share this with us. Now it could be even the case that the issue is way further in the sequence. It needs a detailed observation till which point the board comes up, even if it is for a Brief moment.

Also 700 Ohms is more than suspicious for my taste. Which power rail exactly does measure this low resistance to GND?

[Xruss]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

When you connect the power supply on the KB9022 EC_ON pin appears voltage 3,3v and after 3 seconds drops to 0v.
KB9022 pin unsoldered and fed 3.3v to the bus EC_ON, duty voltages appeared.
KB9022 was replaced by a new one (flashed).

[Xruss]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

So half of the important informations were hidden till now.

If there are voltages present, even for a brief moment then you need to share this with us. Now it could be even the case that the issue is way further in the sequence. It needs a detailed observation till which point the board comes up, even if it is for a Brief moment.

Also 700 Ohms is more than suspicious for my taste. Which power rail exactly does measure this low resistance to GND?

KB9022 was replaced by a new one (flashed).
When you connect the power supply on the KB9022 EC_ON pin appears voltage 3,3v and after 3 seconds drops to 0v.
KB9022 pin unsoldered and fed 3.3v to the bus EC_ON, duty voltages appeared.

[mon2]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

Does the logic board function normally with the EC_ON bypass method?

[mcplslg123]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

I think getting EC_ON for 3 seconds and then going to zero is normal behaviour as it goes into DSW mode.It will get back to S5 state after trigerring only.

[Xruss]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

I searched the internet for information on ADP_ID and found out that my opinion about it was wrong.
Resistance of ADP_ID relative to VDD (+19v) at 65w PSU = 383KOhm, voltage was 0.98v.
After restoring the correct operation of ADP_ID . Laptop worked, problem solved.

[mon2]

Re: HP 15-bw065 (LA-E831P) no EC_ON signal

@Xruss, can you post the details of how you fixed the ADP_ID?