Asus FX504GE DABKLGMB8D0 shorted

[zolie]

Hello,

I'd like to fix it and ask for help here. The error: laptop shorted.

PQ21 was shorted, I changed.
D: 19V S: 10-20mV G: 10-20mV

Can anyone help me solve this error?

Thanks

[mon2]

Re: Asus FX504GE DABKLGMB8D0 shorted

Post the mosfet details. Is it a N-channel or a P-channel type?

Which charger IC is onboard?

If N-channel, the gate must be ~25v to enable. This signal is often driven by the charger IC.

If you have the schematic, link it in the schematic section only, do not post it here.

[zolie]

Re: Asus FX504GE DABKLGMB8D0 shorted

Post the mosfet details. Is it a N-channel or a P-channel type?

Which charger IC is onboard?

If N-channel, the gate must be ~25v to enable. This signal is often driven by the charger IC.

If you have the schematic, link it in the schematic section only, do not post it here.

N-channel, AON6414A
BQ24780s

There is a schematic and a boardview, but the schematic cannot be downloaded. It's in a program. I can attach a picture.

[mon2]

Re: Asus FX504GE DABKLGMB8D0 shorted

Review the details of ACDRV, REGN, ACOK, ACDET on the charger IC. Carefully measure the voltage to ground of each.

Next, confirm if ACDRV pin is ~25v. Likely is not. Locate the ~4k resistor that is often in series on this pin to the 2*DCin mosfets.

Flux and remove this 4k resistor. Do not lose this part. Power up again. Check if ACDRV is now ~25v.

Post each measurement.

[zolie]

Re: Asus FX504GE DABKLGMB8D0 shorted

Review the details of ACDRV, REGN, ACOK, ACDET on the charger IC. Carefully measure the voltage to ground of each.

Next, confirm if ACDRV pin is ~25v. Likely is not. Locate the ~4k resistor that is often in series on this pin to the 2*DCin mosfets.

Flux and remove this 4k resistor. Do not lose this part. Power up again. Check if ACDRV is now ~25v.

Post each measurement.

ACDRV:50mV
REGN:5,9V
ACOK:0,053mV
ACDET:2,5V

After remove ACDRV (PR198): 192mV

[mon2]

Re: Asus FX504GE DABKLGMB8D0 shorted

Can you confirm the voltage to ground on each side of the removed PR198 resistor PCB pad?

Need to be sure that the ACDRV voltage is the side facing the charger IC pin #4.

[zolie]

Re: Asus FX504GE DABKLGMB8D0 shorted

Can you confirm the voltage to ground on each side of the removed PR198 resistor PCB pad?

Need to be sure that the ACDRV voltage is the side facing the charger IC pin #4.

I measured it and the next moment the PQ21 was gone. Shorted, I changed it and after I measured it again. I measured voltage to ground and resistance to ground.

'A': ~200mV (I got no value)
'B': ~0,5mV (80Mohm, than overload)

A short time after the measurement, there is a short circuit again. The power supply indicated. PQ21 heats up.

[zolie]

Re: Asus FX504GE DABKLGMB8D0 shorted

A short time after the measurement, there is a short circuit again. The power supply indicated. PQ21 heats up.

I took it down and looked at it. Its faulty again. I didn't find a short circuit. But there is something somewhere.

[Prutsel]

Re: Asus FX504GE DABKLGMB8D0 shorted

Something is taking too much current. Do you have a Power Supply to inject voltage on the +VIN-line? 1V @ 1A , you can up the Amperage when it is taking the 1A. Feel for a 'Hotspot' on the board. This is a big/thick board so it may take a while before it gets noticable.
+VIN is starting on the current resistor after the Mosfet's. Post your results

[zolie]

Re: Asus FX504GE DABKLGMB8D0 shorted

Something is taking too much current. Do you have a Power Supply to inject voltage on the +VIN-line? 1V @ 1A , you can up the Amperage when it is taking the 1A. Feel for a 'Hotspot' on the board. This is a big/thick board so it may take a while before it gets noticable.
+VIN is starting on the current resistor after the Mosfet's. Post your results

I haven't tried it yet because I found a faulty part. TPN11003NL, PQ97 is bad. Now it is not short circuited. But I couldn't find such a part. What can be replaced? Or if this is missing, can I start the motherboard?


https://www.badcaps.net/forum/showthread.php?p=1263192

[zolie]

Re: Asus FX504GE DABKLGMB8D0 shorted

I replaced the faulty parts and everything is perfect. Thanks for the help!

[Prutsel]

Re: Asus FX504GE DABKLGMB8D0 shorted

Thanks for posting the results.

--SOLVED--