hp spectre x360 dead - please help

[justin35]

hi there,
i have an hp spectre x360 laptop which is dead, nothing happen if you plug the charger, no light no nothing.
laptop is not liquid damage.
i opened it up and say a cracked ceramic capacitor. it's on VIN line. I have attached picture. This capacitor wasn't shorting the line!
Bq715 is charging the battery and creating 13.5 volts for the system (why 13.5v? because i checked on a good laptop)
If i apply 11.5v on battery connector, the laptop is "seeing" the charger and it works without problems...
this cracked capacitor is not an isolated case, it's a well known issue.
according to schematics this ceramic cap is 22uF @ 25v. I replaced it with an electrolytic one 22uF@25v because i don't have a ceramic one, but without luck.
I suspect bq715 might be dead? I don't have a spare one to try... I only have bq25a but i am afraid is not compatible and may damage other things...
anyone encounter this problem?

PS: i attached schematics too. On page 28 is the main power circuit...

[Techtiger]

Re: hp spectre x360 dead - please help

First for Hp’s you have to use original working charger 19.5V/45W, what is the Voltage on PQ1 Drain ? AD_ID ? Voltage on all pin BQ24715?

[justin35]

Re: hp spectre x360 dead - please help

I am using original hp charger for this laptop

pq1 drain- 19.345v
pq1 source- 19.785v
pq1 gate- 19.857v

BQ24715 readings:
p1- 19.339v
p2- 19.339v
p3- 18.039v
p4- 20.226v
p5- 3.3326v

p6- 2.8241v
p7- 0v
p8- 0.39 to 0.41v
p9- 0.39 to 0.41v
p10- 3.7105v

p11- 0.7275v
p12-0.8735v
p13- 0.8726v
p14- 0v
p15- 0v

p16- 6.030v
p17- 5.829v
p18- 0.8718v
p19- 0.8720v
p20- 19.157v


ad_id 0.4357v on connector side....

[digitalpc]

Re: hp spectre x360 dead - please help

u can leave motherboard without this cap, and try. I was thinking BQ chip is the problem...

[justin35]

Re: hp spectre x360 dead - please help

i am sure this boar could work without this cap...
also there is an additional 22uf 25v ceramic capacitor near the 2 in schematics tied one pin to +AC_CHG_IN and one to ground... so there is a total of 3 22uf 25v caps on that line. NOT only 2 as the schematic shows...
i also have some sort of board-view and the 3rd 22uf cap is also missing

i am starting to believe bq715 is the problem...i don't have any to replace sadly
only bq 25a, bq 737, bq 736, bq 728 from donors.
they have same pin out but differs the output circuit diagrams...

[Techtiger]

Re: hp spectre x360 dead - please help

I am using original hp charger for this laptop

pq1 drain- 19.345v
pq1 source- 19.785v
pq1 gate- 19.857v

BQ24715 readings:
p1- 19.339v
p2- 19.339v
p3- 18.039v
p4- 20.226v
p5- 3.3326v

p6- 2.8241v
p7- 0v
p8- 0.39 to 0.41v
p9- 0.39 to 0.41v
p10- 3.7105v

p11- 0.7275v
p12-0.8735v
p13- 0.8726v
p14- 0v
p15- 0v

p16- 6.030v
p17- 5.829v
p18- 0.8718v
p19- 0.8720v
p20- 19.157v


ad_id 0.4357v on connector side....

Check PR103 PR104 for any short it 100K 12.1K if the middle pin adapter have 19V then AD_ID should be +2.5V

[Techtiger]

Re: hp spectre x360 dead - please help

PQ1 Gate Voltage is just 19.85V to switch on the Fet, there is a slight difference Source to Drain

[justin35]

Re: hp spectre x360 dead - please help

Check PR103 PR104 for any short it 100K 12.1K if the middle pin adapter have 19V then AD_ID should be +2.5V

pr103 100 ohm
pr104 12.1kohm
no short on that line


I have another identical board here which is mounted inside chassis and works, and AD_ID is 0.47v of course the battery is out because is dead... i don't know if this matters....

[Vesko356]

Re: hp spectre x360 dead - please help

What is the middle pin voltage reading if the adapter is not connected to the board?

[justin35]

Re: hp spectre x360 dead - please help

What is the middle pin voltage reading if the adapter is not connected to the board?

18.852 v

[Vesko356]

Re: hp spectre x360 dead - please help

18.852 v

It's to high, it should be around 15v or lower, try to power up the board with the different known good HP charger first, or check if your adapter is ok with the different HP laptop.
P.S. Also check PD6 diode at AD_ID line, and continuity between pin 6 at DC jack and AD_ID line all the way to IT8987

[justin35]

Re: hp spectre x360 dead - please help

It's to high, it should be around 15v or lower, try to power up the board with the different known good HP charger first, or check if your adapter is ok with the different HP laptop.

this is the original charger.
I have another laptop same model here, which has a battery issue. it is powering on with the same ac adapter without a problem, so it is not the ac adapter...

[piernov]

Re: hp spectre x360 dead - please help

It's to high, it should be around 15v or lower, try to power up the board with the different known good HP charger first, or check if your adapter is ok with the different HP laptop.

Wrong.
AD_ID at 0.47V is perfectly fine for 45W AC adapter. When floating center pin can measure close to 19V, it doesn't matter. If you touch the probes while measuring it'll drop a bit…

Check if PQ8 is shorted drain/source/gate.

[justin35]

Re: hp spectre x360 dead - please help

Wrong.
AD_ID at 0.47V is perfectly fine for 45W AC adapter. When floating center pin can measure close to 19V, it doesn't matter. If you touch the probes while measuring it'll drop a bit…

Check if PQ8 is shorted drain/source/gate.

Board had a different mosfet mounted in factory 0203gmt. Schematics indicates TPCA8056-H.
I couldn't find much about 0203gmt mosfet, but it was clearly shorted gate to source...
I've found an TPCA8064-H mosfet on a donor board, compared the datasheets TPCA8056-H to TPCA8064-H and the internal schematics is the same. a few differences, and i think TPCA8064-H is "stronger"
Correct me if i'm wrong...
Replaced the shorted mosfet and the board has power now. Works like a charm!

@Piernov - I had a few solution in the past from you also. Again many thanks! You made my day! Keep up the good work! You rock!!!

[Vesko356]

Re: hp spectre x360 dead - please help

Check if PQ8 is shorted drain/source/gate.

Yeah, really good shot.
Well done.
Cheers

[donlan78]

Re: hp spectre x360 dead - please help

Where is pq8 picture please, I’ve seen the schematic but it’s Greek to me without board view file showing where the parts are located,
If anyone has pictures, they can share of the parts they replaced that would be great, i have clean the carbon and replaced burned caps also replaced the BQ battery charging chip,
I can’t seem to find a short on any of the mosfets, if some one can share which chip/mosfet they replaced and where it is located on the board, also how to test mosfets for short, i thought it was done in beep mode Probs on source And drain but I could be wrong
Any help would be great thank you

[Bartoloni]

Re: hp spectre x360 dead - please help

Anyone know what mosfet is this? because it was replaced by another shop and now there is 6426 (N channel 30V) and the laptop is not charging from power adapter after a day of use (yep this is a little strange) .. and is necessary to unplug the battery and re-plug to start again the charging.

(the mosfet was shorted .. drain-source continuity and i replaced it by another 30V N-channel) but the issue is always the same.

the HP spectre x360 is the 13-4110nl mb part n: 849426-601

[Bartoloni]

Re: hp spectre x360 dead - please help

previous shop tell the customer that the mosfet was a DUAL MOSFET .. (and they also burned the battery with hot air .. completely crazy)

P.S. there is also a missing component.. but i think is a capacitor looking at the position.

the board is probably the DA0Y0DMBAF0

[mullspeed]

Re: hp spectre x360 dead - please help

Check if PQ8 is shorted drain/source/gate.

Thank you so much, I've just repaired the same laptop with similar faults and I couldn't get to power up off AC and this was the solution. I don't think I would have found it without you

[bylos]

Re: hp spectre x360 dead - please help

Hi everyone,
First of all many thanks for this amazing thread which helps me to understand the power management circuit of the x360 Spectre.
I've got mine since 2013 and it's surprising still well performing, except for a battery charging issue.
When powered using the AC cable the laptop is working, but the battery is not charging and its level slightly decreasing.

I opened the laptop and changed the battery (the original one was swollen)
Also I noticed that PR91 and one of the 22uF/25V capacitors on +AC_CHG_IN line were completely burnt so I changed them.

I thought that it would be the source of my battery "not charging" but after complete reassembly, the issue remains: The laptop is working but the battery is not charging.

Could you please advice for measurements that I could run to check where the issue is coming from ? For example should I plug AC cable and check BQ24715 pin 19, or +BATCHG net ? Are there any voltage I should expect there with or without AC cable connected ?

Best regards