Dell G3 3579 (LA-F611P) not charging

[Robocop]

Hey guys,

I've seen several questions about this exact issue, but I've never found the fix, so I would appreciate if we can start over the whole debugging process again from start to finish, for my specific issue.

In the BIOS setup, (see pic) the AC adapter is detected with the correct power rating, the battery is stated as charging (when plugged in, of course), and the battery health is stated as "Excellent" (as expected, since this is a brand new battery purchased a couple of weeks ago). However, the battery never charges (the percentage never increases).

The "My Dell" app says "Charging", Battery Health "Excellent", but Charge Rate is "0%/hour" (see pic).

The computer works fine from the battery and from AC adapter.

It really looks like the computer "thinks" the battery is charging, but the current doesn't actually get to the battery.

I tested with two brand new batteries (a noname one, and a genuine one purchased from Dell).
I tested with another Dell AC Adapter (more powerful than the original one) and both are detected correctly in the BIOS.
I also replaced the barrel connector in the computer, but the issue is still there.

Thanks

[mcplslg123]

Resistance between CSOP/CSON pins
Resistance between CSIP/CSIN pins
Voltage on pin17/18/19/21/22/24/8/14/15/16 of charging IC.

No power connected(adapter and battery removed) while measuring resistance between CSON/CSOP & CSIP/CSIN pins of charger IC.

Charger IC used is ISL 9522 or 9538?

[Robocop]

Resistance between CSOP/CSON pins
Resistance between CSIP/CSIN pins
Voltage on pin17/18/19/21/22/24/8/14/15/16 of charging IC.

No power connected(adapter and battery removed) while measuring resistance between CSON/CSOP & CSIP/CSIN pins of charger IC.

Charger IC used is ISL 9522 or 9538?

ISL 95522.

Resistance between:
CSOP/CSON: 2.3 ohms
CSIP/CSIN: 2.6 ohms

Voltage on pin:
8: 5.25V
14: 19.44V
15: 19.45V
16: 2.13V
17: 19.12V
18 5.28V
19: 0V
21: 3.29V
22: 3.29V
24: 3.13V

Note: I connected the AC adapter and the battery to measure those voltages, but the battery was already down to 0V before measuring.

[mon2]

CSOP/CSON: 2.3 ohms

This is ok and expected to be ~2 ohms for the full path.

CSIP/CSIN: 2.6 ohms

This does not look correct. Confirm these measurements again. No power. Meter in lowest resistance scale. This measurement should be ~4-5 ohms. If not, check each resistor that is in the path.

PRB02 + current sense resistor (PRB01) + PRB03 = 2R2 + 0R005 + 2R2 = 4R4 + 0R005 = ~4R5 ohms.

[mon2]

Never mind..just saw the legend to the left that notes that prb02 is 0 ohms for this charger IC.

So this measurement is ok.

[mon2]

Pin 19 (ACIN) is 0 volts?

What is the voltage of pin 7 (ASGATE) on this charger IC which is used to enable the 2*DCin mosfets (gate voltage)?

What is the ACOK voltage?

[mcplslg123]

Pin19 missing voltage as mon2 has highlighted.

[Robocop]

I really read 0V on pin19.
pin 24 (ACOK): 3.12V

You asked "pin 7 (ASGATE)" but according to the schemas, pin 7 is LGATE2, and ASGATE is pin 13 so here are both:
pin 7: 4.82V
pin 13: 1V

[mon2]

Pins 7 (asgate) does not have the correct voltage. This should be boosted to around 25v to enable the dcin mosfets. Suspecting that you have leakage in the dcin mosfets.

watch this video (5:35 onwards is good):

https://youtu.be/9zYTlkU9WGE?feature=shared

ps: this dual package design has me cross eyed - watch the PIN numbers and compare to the video.


Update:

For sanity, posting a partial schematic taken from another logic board for this same charger IC - matched from the share video. It appears that pin #19 is ok at 0 volts (based on this pin definition). ASGATE is still not valid for a normal operation = gate pin driver for the N-channel mosfets onboard.

continued...

your logic board does not make use of the ASGATE voltage.

Share the voltage to ground of the logic gate @ PUB02. Pins 1, 2 and also 4 (output). Measure each.

[Robocop]

Pin 1: 3.2V
Pin 2: 3.07V
Pin 3: 0V
Pin 4: 3.03V
Pin 5: 3.03V

(I don't understand why I get 3.07V on pin 2... I expected 0V (gnd to gnd...))

[mcplslg123]

PUB02 is working perfectly. This diagram is so confusing 'coz of dual usability of two types of charging IC.

[Robocop]

So what would be the next step? Testing the mosfets? How do I do this? 😳