DV5-Board DAQT6AMB8F0 REV:F NO POWER

[auzzie]

Hi to all.

Need help with this laptop DV5 Board DAQT6AMB8F0 REV:F
Found short on Mosfet PQ26 FDS4410A. Used the schematic I found on this forum and followed the short to ground from capacitor PC107 to coil PL12.

Lifted one side of PL12 and the short to ground on Mosfet PQ26 is gone.
Following the schematic next component is the capacitor PC161 which is short.
Removed the PC161 tested it and it is ok but the positive pad on the motherboard is short to ground without the capacitor welded on.

I have the following coil measurements with diode mode on:
Without power
PL7=0.524V
PL8=0.382V
PL9=0.448V
PL12=0.013V

With Power
PL7=0.502V
PL8=0.630V
PL9=0.517V
PL12=0.05V

The laptop does not power on. When I press the power button I get power led on but when I release the button it goes off.
I also have charger port led on.

[mon2]

Re: DV5-Board DAQT6AMB8F0 REV:F NO POWER

Please note that you CANNOT take diode mode tests WITH the power ON.

Always perform DIODE and RESISTANCE checks with all power removed. No battery, no external power adapters.

On this note, remove all power. Meter in resistance mode (2k scale or similar).

Check for low resistance readings on each coil (large grey parts) to ground.

Red meter probe on the coil pin; Black meter pin to ground (shield is ok).

Searching for any low resistance to ground that may indicate a shorted cap that needs attention. Some low voltage rails are normally with a low resistance but share the readings.

Do note that if the resistance is higher than the meter scale, the meter will report "OL" for over-limit - that is a good sign that the rail does not have a shorted cap.

[auzzie]

Re: DV5-Board DAQT6AMB8F0 REV:F NO POWER

Thank you mon2,

Have some measurements about resistance for the coils.
PL7=1.438MΩ
PL8=2.027MΩ
PL9=2.465MΩ
PL12=24.4Ω

Obviously there is a short on PL12 to ground but it is not on any of the capacitors near PC161 or PC160 because I removed both and still have a short.