Console repair: Help identifying components

[newtekuser]

Have a portable gaming console than doesn't power up (power LED stays red when charging and only blinks red once when pushing the power button), upon disassembling it I see what appears to be a blown 0603 component. From what I can tell, it is part of a power regulation circuit.
It doesn't appear to be a diode because when I measure the other two identical components next to it there's no voltage flowing through them. None of the components in this area are shorted to ground and when I measure the other two identical components similar to the burnt black one I get about 0.40 ohm. This tells me this may be a current sense resistor.
I'm guessing this component was blown by the in-rush current from the wifi chip which is in the biggest component in the area. I also don't see any diodes around which is very weird.

As part of the same power regulation circuit I also see three mosfets marked "AHRP 590" but a Google search doesn't reveal anything of use about them. I'd like to see if any were taken down with the blown component if I can find any data sheets for them.

In the two pictures you can see the board before and after cleaning.

Can someone confirm if this is indeed a current sense resistor?
What about the mosfet?

[fzabkar]

The manufacturer of AHRP is Monolithic Power.

Edit:

MP8765GQ, Monolithic Power, 24V, 6A High Efficiency Synchronous Step-down Converter with Hiccup OCP, PWM/PFM mode pin and output discharge, marking AHRX+XXX, QFN3x3-16P:

https://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MP8765/

http://markingcodes.com/search/c/ahr


Edit #2:

Could the "current sense resistor" be a ferrite bead?

[newtekuser]

The manufacturer of AHRP is Monolithic Power.

Edit:

MP8765GQ, Monolithic Power, 24V, 6A High Efficiency Synchronous Step-down Converter with Hiccup OCP, PWM/PFM mode pin and output discharge, marking AHRX+XXX, QFN3x3-16P:

https://www.monolithicpower.com/en/documentview/productdocument/index/version/2/document_type/Datasheet/lang/en/sku/MP8765/

http://markingcodes.com/search/c/ahr


Edit #2:

Could the "current sense resistor" be a ferrite bead?

Thank you for the link! I went with my gut feeling and ordered some current sense resistors since I could not find ferrite beads of the same resistance. I also ordered a few of the MP8765 buck converter ICs just in case since they're cheap.

[fzabkar]

I would make sure that the load side of the DC-DC converter is not shorted or overloaded.

[wraper]

Blown component is a ferrite bead. Exact value not important, what matters the most is if it can handle enough current. FWIW you can replace it with a jumper and circuit will work just fine. Although I doubt it blew by itself, something else should have failed and caused a very large current flow. You should check if either side of the ferrite bead is shorted to GND.

[wraper]

I see another ferrite bead above it that is either blown too or mechanically damaged.

[newtekuser]

I see another ferrite bead above it that is either blown too or mechanically damaged.

I found several components shorted:

Top step down converter: PIN 9 (SW), PIN 8 (SW), PIN 6 (MODE) shorted to ground
Middle step down converter: PIN 6 (MODE) shorted to ground, PIN 5 (NC) shorted to ground (connected to GND on purpose?)
Bottom step down converter: PIN 5 (NC) shorted to ground (connected to GND on purpose?)

None of the components identified as ferrite beads are shorted to ground, but I found about six of 0201 caps shorted to ground to the right of the inductors as well as a larger polarized cap (what is this packaging/size?) to the right of the top inductor.

[fzabkar]

I doubt very much that those capacitors are faulty. It's much more likely that an IC is shorted. I'm talking about those ICs that are powered from these stepdown converters, not the converters themselves.

It would help if you could provide a photo of the whole PCB.

[newtekuser]

I doubt very much that those capacitors are faulty. It's much more likely that an IC is shorted. I'm talking about those ICs that are powered from these stepdown converters, not the converters themselves.

It would help if you could provide a photo of the whole PCB.

Attached full PCB picture. I can only probe the Winbond flash chip which is not shorted, and I'm not able to get to the Super IO (ITE) IC, RAM or the CPU pins. From what I could gather on the Internet, the Super IO chip is what frequently goes out on the Steam Deck. None of the capacitors surrounding it are shorted though.

I did manage to probe some of the caps on the CPU and they're shorted to ground, so hope it's not game over.

[wraper]

What actual resistance is that "shorted"? CPU/GPU and RAM may have very low resistances on their power rails. Also those converters can easily get shorted to the ground.

[newtekuser]

What actual resistance is that "shorted"? CPU/GPU and RAM may have very low resistances on their power rails. Also those converters can easily get shorted to the ground.

Ah, I forget that these have very low resistances  I measure 4 ohm on one side and 0.3 ohm on the other side of the resistors.

[wraper]

Resistance may be fine depending on what power rails those are. I'd expect converter IC to be dead if a ferrite bead in its input failed open/burned. The issue is that if upper mosfet (between Vin and out) inside the IC fails short first, it may take out (overvolt) the load as well.