Hp pavilion 14 - No display

[Nagyesz]

Hi all,
Model: HP Pavilion 14-ce3010nh 8BV97EA
Board number: DAG7ALMB8C0 - G7AL REV C
Issue: I have an HP Pavilion 14-ce3010nh 8BV97EA laptop. When plugged into the charger, it turns on, but there is no display, the fans do not run, and the processor gets slightly warm. Unfortunately, I haven't been able to figure out what the problem is. I've reflashed the BIOS twice without any success. No post. Already tried out with another ram stick with no luck

I measured the voltage with the HP turned on in red, and I measured their resistance with the HP turned off in green. (I measured the resistance in 200 mode)


How should I continue, what could be the problem?

Thank you in advance for any ideas!!!

[mon2]

Hi. If available, link the schematics but only in the dedicated schematics forum.

What is the history of this laptop?

Original power adapter? Which charger IC is onboard? Post pics of this area.

Measure the voltage to ground of the dcin mosfets that often follow after the power adapter.

What are the topside markings of the dcin mosfets?

[Nagyesz]

I only have a boardview:

I bought it as faulty a few months ago from my friend, and I have been trying to figure out what's wrong with it for a few days now

I'm using 19.5V 2.31A power adapter, HP original one

Charger IC area (?)


Please help me locate the DCIN mosfets ( on the boardview component name or just in any way)

[SMDFlea]

LINK to boardview - -> https://www.badcaps.net/forum/troubl...ic#post3211163

[mon2]

Locate mosfets PQ1 and PQ2. Measure the voltage to ground on each pin of these mosfets. Charger IC is at PU1. See the linked schematics in the above post.

[Nagyesz]

@PQ8101 (also PQ8100)


1-2-3 pin 19.4 V
4 pin 24.6
pin 5-6-7-8 19.4V


@PQ8102


With battery connected:
pin 1-2-3 13 V
pin 4 11 V
pin 5-6-7-8 18.7 V

Without battery:

pin 1-2-3-4 0V
pin 5-6-7-8 19.4V


Couldn't find @PU1 (didn't find anything similar)

Measured the values while it was turned on.

[mon2]

Do not have access to the actual schematic so you will be our eyes and ears on this repair.

You are in the proper area with PQ8101. Based on your measurement, the gate voltage is correct to enable this N-channel mosfet.

Who is next? Inspect the same details on the mosfet that follows. Post pics as attachments of this area. The charger IC must be nearby these parts. The last post did not come through on the pics.

[Nagyesz]

@PQ8100 after PQ8101
1-2-3 pin 19.4 V
4 pin 24.6 V
pin 5-6-7-8 19.4V

(Boardview has been quite useful so far, unfortunately, I don't understand schematics.)

Pics from above:
@PQ8101


@PQ8102

[mon2]

Locate what you believe to be the charger IC and share the full topside markings. We can then search on Google to check if the device is indeed a charger IC or not.

In the 2nd pic, there is the battery connector so you are close. The dark mosfet to the left of the inductor appears to be discolored. Perhaps it is defective. You can test any mosfet with resistance checks.

Remove all power (never any power when checking in resistance or diode mode). Measure the resistance across the mosfet:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Checking for a low resistance measurement. Post all measurement. If you see an 'OL' then you must use a higher resistance scale on your meter unless the meter is auto-scaling.

[Nagyesz]

The dark mosfet to the left of the inductor appears to be discolored

That's @PQ8102

"With battery connected:
pin 1-2-3 13 V
pin 4 11 V
pin 5-6-7-8 18.7 V

Without battery:

pin 1-2-3-4 0V
pin 5-6-7-8 19.4V"
___________________________________________________________________

1-2-3 to 5-6-7-8 is 2.4M ohm
1-2-3 to gate 4 is 6.3M ohm
4 to 5-6-7-8 is OL every mode

Can @PU8100 charging controller?

[mon2]

Yes, that is the charger IC:

https://www.renesas.com/us/en/produc...mbus-interface

[Nagyesz]

Should I measure the voltage on each pin?

[mcplslg123]

As per your post#3,charger used is 19.5V,2.31A=45W.Too low for gaming unit. Check the rated adapter for this unit and i think it should be 130W or higher.
No point probing the charger IC or dc-in area as no fault indicator in your measurements so far.
You have 5V/3V/1.0V/1.8V- a good indicator of some life. I'll suggest to flash original bios back as no indication of bios fault can be observed at this stage.

Next rail which is missing is 1.2V for RAM and your entire focus should be on RAM IC.Check whether you have enables for it.
Dont follow hit and trial method without being sure.This will lead you no where and may even worsen the symptoms. patience and deep understanding is the key to success here.

[Nagyesz]

Thank you for the response and all the tips so far. The biggest charger I found is 150W, and there's also a 120W one. I haven't decided which one to buy yet, but I'll have it by tomorrow.

My question is whether I can continue measuring the RAM IC with this weaker charger?


Edit: I looked into it, and they recommend a 65W power supply for it. Would it be a problem if I bought a 120W one or 90W?

[Nagyesz]

I did a bit of investigating, and I think I've found the problem. I'm not exactly sure which component it is, but I'm certain the values are not correct. ( ram inside, 45W supply)





@PQ8300 pin 5 19.41V pin 1-2-3-4 0V




@PR8306 pin 1-2 4.77V
@PU8300 11 pin 5.13v 12 pin 5.13v 18pin 4.77v pin 9 2.11V
@PC8308 pin 1 4.77 pin 2 0v
@PC8307 0v both
@PC8317 pin 1 5.13V
@PR8305 pin 2 19.4V pin 1 2.11V


What is my next step?

[mcplslg123]

I doubt whether the recommended adapter is 65W. Make sure by getting as much info on this. However, if you are sure about 65W,then you can buy either a 65W or 90W-no neeed to buy 120W.

I dont see anything wrong in measurement of PU8300. Howver, the most important pins are missing.

measure voltage on pin 7-8 of this IC.

[Nagyesz]

@PU8300

6-7-8-10 pin 0V
9 pin 2.11V
11 pin 12 pin 5V
pin 13,14,15 0V
Pin 18 4.77V
pin 1-5 0V
pin 20,19,17,16 0V

[mon2]

Review the pics from post # 15 - there appears to be a pimple on the chip in the letter ‘E'. If true, this part is probably defective and is an ITE EC controller. Post a clear of this part.

[Nagyesz]

I don't quite understand what I should be seeing. I have taken two more visible pictures.

[mon2]

Note the bubble in the letter ‘E'. Top half of the letter.