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.
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.
Attached Files
