MSI DELTA 15 NO POWER

[Kevin555]

Hello I have a problem with an MSI DELTA 15 which does not want to turn on according to the customer he was on the internet and the PC suddenly shut down while it was on battery he then tried to charge but nothing apart from the white charging LED which lights up, after disassembling I tested different voltage and I encounter a problem with the 3v 5v chip which does not receive its activation signal of 3.3volt I do not I have no diagrams or Boardview at my disposal but in my opinion this signal should be sent by the EC chip (ENEKB9028GC) on my thermal camera I only have 2 heating points the 3v 5v chip and the EC chip do you have an idea of the problem and where should I look?

( https://ibb.co/album/jZZsFN )

[mon2]

Which charger IC is onboard?

Review the charger sticky above by piernov

Using the official and recommended power adapter?

[Kevin555]

Which charger IC is onboard?

Review the charger sticky above by piernov

Using the official and recommended power adapter?

Thank you for your response

The charging chip has the reference (BQ24780S) and yes I use the original power bank here are the photos of the chip and the power bank.

[mon2]

Perfect. See attached for the TOP side view of this charger IC.

Remove all power. Disconnect the battery. Meter in resistance mode.

Measure the resistance to ground of the ACP and ACN pins on this charger IC. One meter probe onto pin #1 or # 2. Other meter probe to ground. We are checking if there is a short on the main power rail that powers this logic board.

What is the resistance to ground?

Are your meter probes pointy to measure the pins on the charger IC? For resistance check, no issue but need to be pointy for voltage checks so the pins are not shorted.

[Kevin555]

yes my probes are pointed my multimeter in diode mode and red probe to ground ACP (0.420) ACN (0.420).

[mon2]

Diode mode is different than resistance mode. But the diode mode measurements do not show this main power rail as being shorted. This is a good start.

Now, apply the power. Meter in DC volts mode (30v or higher scale). Measure the voltage to ground on the

ACDRV pin # 4 ; should be ~25v if all is ok and is used to enable the 2 x DCin mosfets in the power path
ACOK pin # 5
VCC pin # 28 ; used to power the IC
REGN pin # 24 ; must be ~6 volts stable if all is ok

[Kevin555]

all voltages are good ACOK (3.3 volt)

[mon2]

How hot are the missing 3v and 5v regulators? Often these parts are enabled using 2 resistors that are driven by the main power rail (same voltage as you will see on ACP/ACN pins). The resistors create a safe lower voltage which is fed onto the ENABLE pins of each regulator.

What is the voltage to ground on the ACN/ACP pins? It should be the power adapter voltage since the charger IC is enabling the power path mosfets.

If the 3v/5v are missing, then power down and measure their resistance to ground at their inductors. If a low resistance, then someone is shorted on that rail. No power during resistance checks.

[Kevin555]

The temperature is around 35 degrees celsius I did not specify but I have already changed the 3v 5v chip without success, ACN and ACP I have 20v here is a diagram of the 3v 5v chip with the voltages that I should have I put a cross where I have no tension.

[Kevin555]

here is the 3v 5v chip

[mon2]

The measured temps are not considered to be hot.

The '2N=' marked part is

Richtek # RT8249CGQW




Full datasheet:

[mon2]

Measure the voltage to ground of:

EN1
EN2
LDO3
LDO5

on this IC.

[Kevin555]

EN1 : 0
EN2 : 0
LDO3 : 3,3v
LDO5 : 0

[mon2]

OK. LDO3 (only) on is good and follows the part markings.



Check the resistance to ground of LDO5 and the output rails on this regulator to be sure there are no downstream shorts.

You will have to trace where EN1 and EN2 are enabled. As per your first post, is it the EC or is it a resistor based enable using 2 resistors that are feeding from the main power rail?

Often there are 2 resistors building a voltage divider to lower the 19v to a safe enable voltage for EN1 and EN2. Hunt for these parts using diode mode and a tone beep.

If mating with the EC, then the EC power rails and clock must be confirmed to be ok.

[Kevin555]

Okay thank you for all the details I really appreciate your help it's late at home I'm going to rest and tomorrow I'll give you everything you need, good night sir.

[Kevin555]

Hello so I checked the 2N chip completely I didn't find any output short and I found where EN1 is connected I switched to diode mode and I have a direct connection with the pin of this IC I don't know what to it is useful I do not have its datasheet but on the second identical IC right next to it I have no direct line for EN2

[mon2]

https://www.mouser.com/datasheet/2/2...HOxYWdLUoMcLNX

[Kevin555]

I checked and this AE chip does not have its activation voltage either which passes through a 10k ohm resistor, i just have the VIN on pin 1
no shorts either

[mon2]

Do not have any schematics for this board. You will have to trace the enables and hunt for faults. Test each inductor to check if the voltage is within spec. Perhaps bios is corrupted. Check spi lines for activity.