HP Envy x360 13-bf0013dx (i7, 8gb) ipa32 la-m024p rev 1b short near PJ1802, type-c not switching to 19 volts

[u666sa]

Laptop is HP Envy x360 13-bf0013dx, hp website link, it's an i7-1250U with 8 gig onboard ram.
Platform: ipa32 la-m024p rev 1b



Originally you'd plug power supply into it and it would take up to 1.2 amps and then drop to 200 milliamps and then go back up again to 1.2, staying all the while at 5 volts. Pressing power button would results in power LED blinking amber 3 times. 3.3 volt rail, 5.1 volt rail present, main power rail 8.8 volts. Power button test pads near EC chip 2.7 volts.

I found a short on the other side:



My scissors are pointing to the pad that is shorted to ground. As you can see from picture, I have removed solder on JP8102 and also blown aside FU2 fuse. Without this, coil PL1801 would get really hot. Presently there is 1.8232 volts on PL1801. However, pressing power button does nothing and type-c stays at 5 volts, 180 milliamps. Power button test pads near EC chip now show 3.0 volts.



I wonder where that pad is going? Maybe somebody come across this? Without boardview or xrays I want to sweep the board using some wire mesh.

COILS.

Main power rail 48k
3.3 rail 15k
5 rail 139k

coils near CPU
181 ohm
30 ohm
16.2 ohm
15.8 ohm
28 ohm

coil near touch connector
140 ohm

coil on the other side
56 ohm


There was also something else. Chip under WiFi module had corrosion. Removed it and fixed. Also tried powering without it. This had no effect, nor it was shorted. Just some corrosion.

[Rudolfl]

Did you figure this one out? I have one doing same. Doe snot negotiate 20V without battery, but does if battery is connected. Doe snot power on. I suspect BIOS, but was wondering if you got yours running

Rudolf

[u666sa]

What's your resistance on rails? Check all. Pay attention to this one as well. PJ1802 to ground. Mine was dead short. SHORT CPU. Actually short on the hub, smaller crystal on CPU, and that thing apparently is replaceable. I let this one go. Client was a black girl who didn't pick up her notebook for 3 months after this, refused to pay $20 return shipping coming up with excuses, probably waiting on me to get rid of it so she could scam me. She did made an attempt to send apple cash, then it bounced.... Bleh. Pick your clients better. Plus this thing could be bought for about $150 used, if you want it. If you want a brand new, used, board it's just around $100. Plus $50 for labor, and it's $150 for the whole job. I'm glad I didn't offer her this route, because I don't think I'd be getting paid.

Here is another thread on it -- https://*******/viewtopic.php?f=53&t...13+bf0013dx%2A

It's vlab dot su before that slash, su is old top domain name from the start of internet, it's for Soviet Union.


P.S. original client message on question tell me what's wrong with it

[Rudolfl]

Thanks, will check
At the moment I suspect BIOS problem. My programmer is playing up, waiting for new set of clips, so have to wait till they arrive so I can test.

And thank you for sharing the link. Btw, I can speak Russian and can translate if you need anything

Rudolf

[Rudolfl]

In my case i seem to have all voltages present. Did try the point you suggested. Normal 1.8V there. 3.3V is OK too.
Tried to re-flash BIOS and EC EEPROM (one at a time) -- same. Signals around EC chip are also OK. So, not sure what else is going on. Will keep digging

Rudolf