Asus Rog GL703G/Battery Connector Short

[mon2]

With no power, meter in resistance mode (not diode mode), measure the resistance to ground of each of the battery connector pins.

concerned about the 6 pin part that is with the ‘c34’ topside markings. Suspecting this to be an esd device. This device, if shorted, will tank the smbus communication with the charger ic.

if convenient, flux this c34 part well and remove it off the board. Then measure the resistance to ground again of each of the battery connector pins. Do not lose this part. We may need to place it back. Protect plastic parts from heat with aluminum foil.

[mon2]

See attached. Measure the resistance measurements without a power adapter and without a battery.

[GlassMonolith]

Measurements using the power connector as ground still, are;

Pin 4: 0.83kΩ
Pin 5: 0.67kΩ
(I may have the pin numbers backwards)

If this isn't conclusive enough, I'll remove the esd, I'm just slightly intimiated by how small it is.

[mon2]

These smbus / i2c lines are not shorted.

In the earlier post, the M3058 mosfet near the battery connector was measured? It appears to be shorted. Suggest to flux it and remove off the board for testing again while it sits on your work bench. Allow it to cool and be patient for the solder to melt. Then lift up with tweezers. Then measure it again.

Do you have a replacement ? There are other mosfets that can replace this one from Digikey or mouser or Texas Instruments.

[GlassMonolith]

Yes, that one was measured in the same post 2 or 3 ago with the two Nikos mosfets. Measure again with resistance off the board?

I have no replacements to anything at the moment. Which chip would you suggest as replacement?

[mon2]

Attached is the datasheet of the original mosfet.

Here is a suitable replacement:

NTMFS0D9N03CGT1G onsemi | Discrete Semiconductor Products | DigiKey

Here is another (this one is from Texas Instruments):

CSD18510Q5B data sheet, product information and support | TI.com

Often, you can create an account and request a free sample which will probably be filled by Digikey or Mouser or TI.COM website with rapid shipping.

[GlassMonolith]

Awesome! I meant to reply earlier, but I've ordered the mosfet, so hopefully that gets in soon and I'll update again. Thanks for all the help so far!

[GlassMonolith]

Okay, so as of now after swapping that new mosfet, I still get no power on either battery or just power cable.

What should I check next?

[GlassMonolith]

What should I check next? Anything I should go back and verify?

[GlassMonolith]

mon2

[mon2]

See attached. These are the DCin mosfets. Measure the voltage to ground of each pin with the power adapter connected.

[GlassMonolith]

DC voltage?

Top pins of upper mosfet measure 19v, all other pins on both mosfets meter somewhere between 0.01 and 0.02

[mon2]

Continue to review these mosfets. Meter in resistance mode. Remove all power.

Measure the resistance across these mosfets again.

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

post each measurement for each mosfet.

[GlassMonolith]

mon2

Top:
S+D= 9.2m
S+G= 4.7m
G+D= 10.8m

Bottom:
S+D= 9.0m
S+G= 4.6m
G+D= 13.0m

[mon2]

These mosfets are not shorted but not turning on.

With no power, measure the resistance to ground of the drain pin of PQ8902. This is the main rail for the logic board. Checking if this main rail is shorted.

[GlassMonolith]

mon2

I'm unsure which one would be pq8902.

[GlassMonolith]

[nickstyle]

Did you check for short after the second mosfet? I`m sure the main power rail is shorted and you nees to pus some voltage and check with alcohool or a thermal camera where is the short.

[mon2]

PQ8902 is the mosfet that does not have the 19 volts. The first mosfet that is mated with the DCin adapter has its drain pin connected directly to the raw power pin.

[nickstyle]

Did you check if the second mosfet is shorted to ground?