Trying to identify blown component HP ENVY x360 - 15-cn1511na

[Sephir0th]

Pin12 and 13 at the BQ25708 are the Clock and Data Pins. Here you can confirm the values being low for sanity. Other than that, sure, remove the array and see. If the value stays low, than it still applies what i wrote above. The EC and/or the charging controller is fried on this track.

the diagnose is already done then. Cure with power supply in combination with thermal camera or by removing possible suspects.

[pasqui]

Here are the voltage measurements i just took, with the board out of the chassis (so the laptop is off):

• With only the battery connected:
  • Pin 12: 3.19 V
  • Pin 13: 0.357 V
• With only the charger connected (no battery):
  • Pin 12: 0 V
  • Pin 13: 0 V
• With both battery and charger connected:
  • Pin 12: 3.25 V
  • Pin 13: 0.357 V

[Sephir0th]

Here are the voltage measurements i just took, with the board out of the chassis (so the laptop is off):

• With only the battery connected:
  • Pin 12: 3.19 V
  • Pin 13: 0.357 V
• With only the charger connected (no battery):
  • Pin 12: 0 V
  • Pin 13: 0 V
• With both battery and charger connected:
  • Pin 12: 3.25 V
  • Pin 13: 0.357 V

You were supposed to take resistance measurements, same as before. However, the low voltage at Pin 13 tells already that something is wrong here.

Once again, charging Controller and/or EC fried.

Awaiting resistance measurements which would confirm the values which were taken earlier.

[pasqui]

The resistance is the same 11,67 kΩ! If this BQ chip is fried, could you help me figure out which exact package I should get? I see there are several versions like BQ25708, BQ25708SRN, etc!

[Sephir0th]

If it is 11.67 KOhms then it is NOT the same!

Not sure what you are doing here, but the point was to compare the resistance to GND values of Pin 3 (219 Ohms) and 4 ( 137KOhms) of the battery connector with Pin 12 and 13 of the charging controller.

And when you share only one value from what Pin is it? From Pin 12 or from Pin 13?

We can not continue until you start attentive following the advise and until this is sorted.

[pasqui]

Hi, sorry for the delay in getting back to you, I've been really busy lately.
I’ve now done the resistance measurements between pin 3 (BATTERY) and pins 12 and 13 (BQ chip), and between pin 4 (BATTERY) and pins 12 and 13 (BQ chip):
Pin 3 - Pin 12 = 11,85 kΩ
Pin 3 - Pin 13 = 11,85 kΩ

Pin 4 - Pin 12 = 134,1 kΩ
Pin 4 - Pin 13 = 134,1 kΩ
Could you please provide me with the exact steps to follow for any further measurements you’d like me to take?
Thanks again for your patience and support! I really appreciate it. By the way, I just subscribed to your YouTube channel!

[pasqui]

If it is 11.67 KOhms then it is NOT the same!

Not sure what you are doing here, but the point was to compare the resistance to GND values of Pin 3 (219 Ohms) and 4 ( 137KOhms) of the battery connector with Pin 12 and 13 of the charging controller.

And when you share only one value from what Pin is it? From Pin 12 or from Pin 13?

We can not continue until you start attentive following the advise and until this is sorted.

I apologize, but i’m still new to this field, so i kindly ask for a bit of patience. That’s also why i’m asking if it would be possible to receive some well defined guidance or support to help me identify the short circuit (I’m sure something is shorted, but I can’t figure out exactly what).
Anyway, i do have the necessary tools, such as a bench power supply and a thermal camera, so feel free to ask for any test or measurement you think might help!
Thanks again for your time and help, i really appreciate it! <3