HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

[mon2]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

replacement board

You ordered the complete logic board and it does not charge???

I am with @reformatt, the adapter is not being sensed to be powerful enough. Test others. HP uses a resistor to define the power rating of the adapter.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

I've already checked continuity from the adapter's center pin to the board and it's OK. Also the center pin voltage on the board changes - it's 820mV with the original 135W adapter and 682mV with 60W or 90W adapter. It does not charge with any of them...

Maybe the fault is so common that the "new" board has the same problem?

[mon2]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

This adapter ID voltage is too low. So low that it will take a precision analog to digital converter to detect the adapter power.

Review this website:

https://wiki.robotz.com/index.php/HP_Smart_Pin

Use external resistors to dial up ~5-6 volts onto the target dc adapter center pin on the logic board.

Then test again.

[mon2]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

A more detailed article on the same topic:

http://nerdipedia.com/wiki/tiki-inde...laptop+charger

Do update this thread after testing these ideas.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

According to some other posts, the center pin voltage is probably correct.

When the center pin is not connected (removed from the connector that plugs to the board), the power jack LED does not come on at all.

[piernov]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

This adapter ID voltage is too low.

The voltage can vary between boards model since it depends on the bottom resistor of the voltage divider on the board.

Use external resistors to dial up ~5-6 volts onto the target dc adapter center pin on the logic board.

Doing so could damage the board.

[mon2]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Can you link or post the schematic for your logic board?

Does this model also offer a usb C port for charging?

Thanks @Piernov. Thought the same but others are reporting success with this adapter pin voltage. Best for us to review the exact resistors / protection of this pin on the EC on this model.

I think the fault is due to the EC unable to detect a valid pin voltage to define the proper adapter for charging.

For safety, keep this pin under 3v3 which will likely be the max raw voltage of the EC's gpio pins.

Still of concern is why the logic analyzer spews different smbus traffic between the batteries.

Also a good read:

https://www.badcaps.net/forum/showthread.php?p=1099382

[reformatt]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

At this stage, I would normally try to find another working unit for a sanity check to find out what does and does not work, be it batteries, adaptors and logic boards. You've done well to perservere so far!

I remember seeing a case with a MAC not charging after trying 4 batteries. The assumption was that it was a logic board fault only to find out that all 4 were indeed faulty.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Discovered some more FETs on the back side of the board (completely covered by black plastic sheet)!

There are two AC switching FETs and three that look like bypass FETs from ISL9241 datasheet. As they were nowhere to be found (and there's no schematic), I thought that there was no bypass.

There are two 0203GMT (AP0203GMT) (in parallel) on VADP side and one M3092M (QM3092M6) on VSYS side. There's G-S short! Used bench supply to force current through the short and looks like the short is in QM3092M6.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Removed QM3092M6 and it's really shorted G-S. S-D looks good, however. No more short on the board.
Replaced by FDMS0310AS (from a dead board). It's charging now!

[reformatt]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

So both boards had the same fault then?

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Yes, the "new" one has the same short. Haven't fixed it, will try to return it instead. Seems to be a common failure.

[mon2]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Charges both batteries?

Before this discovery, the smbus traffic was different for each battery pack.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Yes, it charges both batteries.

[reformatt]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Excellent. Both boards being faulty is why I do the sanity check with another system. You assume the replacement board was 100% working, but turns out it wasn't.

Biggest lesson I was taught in electronics as a trainee was that when you assume something it makes an ASS out of U and ME.

Full marks for persistence though. A lot would have given up.

[mon2]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

it makes an ASS out of U and ME.

It is from a old Benny Hill skit (UK):

https://www.youtube.com/watch?v=bPsg42EKJic

He used to push the censors back then.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

Attaching photo of the shorted FET.

[reformatt]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

So I've had a 15-df that I've been struggling with since December. Original battery was swollen. Replacement from supplier seemed to work initially however customer states that it only last 5 minutes and switches off. Another replacement charges, sort of.

Battery is SU06XL and doesn't seem to be stocked by many suppliers. So I've had to resort to getting a battery directly from HP reseller (EMPR) for twice the price.

Will wait to see how this battery goes first, but may very well be a board issue.

[Rainbow]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

I've been unable to find a new HP SU06XL battery. Luckily, the original one was OK (88% capacity, not swollen).

Are there any replacement batteries that don't trigger the stupid BIOS warning?

[reformatt]

Re: HP Sprectre x360 15-DF DAX38CMBAG0 (Quanta X38) not charging

The first battery seemed to be ok, however he reported that it'd last 5 minutes. The 2nd battery when I tried to charge by USB-C, rather than the barrel adaptor, current went haywire on my ammeter. He said it wasn't charging with the barrel adaptor.

This is the reason I got out of the phone repair industry. So over parts that just don't work out of the box. We are now starting to see it in the computer industry now too.

So I bought the latest one directly from HP/EMPR. Nearly AUD $200 with shipping, whereas everyone else is AUD $100. That's the price you pay to get something that actually works.