HP Pavillion G6 No power/full short-URGENT

[drazy004]

Good day everyone. Please I need urgent assistance concerning an HP Pavillion G6 laptop that I'm working on. The original fault was that it only powers on without the battery plugged in. If the battery is not removed, the laptop will neither power up on battery or adapter. I decided to change the IC marked PU8 on the Schematics which I downloaded. Unfortunately for me, for some not completely strange reason, my ho air gun (a Bakku 8032A with adjustable control for Temp and Air speed) didn't come up as hot as usual (later found out it was due to the low voltage from t mains). Hence I found myself having to spend more ti heating the component up as well apply more soldering past than normal. Unfortunately when I plug the board to its adapter now, it shows a dead short. The light on the adapter goes out. I've tried to locate the source o the short, but I don't seem to be able to. Everything just appears to short to ground.
Right now I Think I've hit a mental block and I need advic on what to do. I'm a tech with decent skills re soldering and electronics, but relatively new to reading schematics so please feel free in making recommendations. I've attached a copy of the schema diagram a well as actual pictures of the board. Thank you all.

[meritosari]

Re: HP Pavillion G6 No power/full short-URGENT

"The light on the adapter goes out", symptom +vin line have shorted

You could remove PQ50 to isolate circuit first. Measure resistance on circuit on the pads of PQ50 then decide where it's the shorted still remains, whether goes to on right side of schematic, otherwise.

[drazy004]

Re: HP Pavillion G6 No power/full short-URGENT

Thanks for taking interest meritosari. I'll follow your suggestions and post my findings before the end of the day. I appreciate.

[sancheti81]

Re: HP Pavillion G6 No power/full short-URGENT

Check near battery connector caps or mosfet may short

[drazy004]

Re: HP Pavillion G6 No power/full short-URGENT

Sorry guys, I thought I would be able to post updates yesterday. Unfortunately there has been total blackout since then till now, which means I can't really do much. However I have tested the mosfets you talked about @sancheti81, and yes they are short. I believe things will get clearer after removing PQ50 as merisotari pointed out. I wish I had a nice power supply that holds even on short circuits. Mine shuts down when it's connected to a short circuit.

[drazy004]

Re: HP Pavillion G6 No power/full short-URGENT

I've been able to remove PQ50 from the board. Unfortunately, the board is still short. Please how do I localise the main culprit component(s). Thank you everyone and I apologise for the delay

[meritosari]

Re: HP Pavillion G6 No power/full short-URGENT

https://www.badcaps.net/forum/showth...+short+circuit

https://www.badcaps.net/forum/showth...+short+circuit

BTW, I wonder, when first your problems are the unit can't turn on from battery but working fine from adapter, Why you've touch (replace) PU8, if working from adapter then PU8 has be working fine.

[drazy004]

Re: HP Pavillion G6 No power/full short-URGENT

I misunderstood the schematics. I gess shd have been PU9?

[meritosari]

Re: HP Pavillion G6 No power/full short-URGENT

When first problem it might be PQ23 have issue, at this moment seem +vin shorted to ground. So You must be chasing what the cause +vin line has short cicuit. This line was spread on many points. could be caps, mosfet or IC as the causes

The quick way is use lab bench PSU, also can remove the component one by one (frustrated way, but you can learn something valuable from this process)

[drazy004]

Re: HP Pavillion G6 No power/full short-URGENT

I found pin 3 of PQ50 shorted. All other pins are not shorted. Pin 3 is connected to PQ23 via some resistors and capacitors