Alienware Area 51M Monster Dual Jacks, 1 Shorted

[mgrharry]

Alienware Area 51M laptop. This monster has an i9-9900K desktop CPU and replaceable GPU. For full performance it requires two power adapters. The system works, but complains of insufficient power when posting with only 240W adapter connected. Unfortunately there is a short to ground on one of the power rails so the secondary power adapter cannot be utilized. In testing there is a short across the pins of DC in connector so it seems like it should be an obvious short on a component like tvs diode that has blown to protect board. The shorted jack trace goes through board and on the other side there are a bunch of shorted components where it comes out. But I haven't located the source of the short. Some photos are attached. As usual, for your expertise and consideration.

[Stevedb]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

So if i understand it good you have a short on the input from dc jack. If that is the case then you must measure the pins without dc jack. So the dc jack is shorted itself or component around . If you got a shorted power rail after current sensor then you need to give resistance to every coil on 200 ohm stand from you multimeter without any power and place the values on hd picture front and back and upload also shematic.

[ktmmotocross]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

as laptop works u must have short to ground before second mosfet. u can inject 19V 0.5A /or similar 10W/and search for heating component with pouring IPA. i bet u find shorted capacitor

[mgrharry]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

DC jack is not shorted, short is on the board itself. I removed CPU and tried injecting 1v 3a at the point indicated in the attached pic but couldn't locate any particular component heating but perhaps that was past shorted component? Where best to inject? And 10W injection seems relatively high, if it's just a shorted cap shouldn't lower injection been enough? I've also attached two additional close crops with markup for clarity.

[JaroTech]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

Hi, can you remove PQS10 and check if the short is before (Pin 1) or after (Pin 5) of PQS10.

[mgrharry]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

PQ10 is EMZB08P03 https://datasheetspdf.com/pdf-file/1...S/EMZB08P03V/1

No short on pin 1, but pins 5-8 are all shorted, as are PQS01 and PQS03 on other side of board.

[JaroTech]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

Ok, remove PLS01 and check if the short is on PRS01 or PQS01 pin 5.

[mgrharry]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

With PLS01 off, there is no short on PRS01 but PQS01 pin 5 (and the rest) is shorted.

[JaroTech]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

What you have directly connected to ground on the PQS01 pin 5 line are 7 capacitors or 5. PSC01, PSC02 and PSC03 are next to the PLS01. PSC71 and PSC72 are next to PQS03. PSC2508 and PSC2509 are above PQS03, but from your pictures they seem not installed, they are used for EMI debugging. You can start with PSC03, and the others if the short is still there.

[DanielDacko]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

I think this is getting complicated without need. Remove the DC jack and inject voltage like marked on the picture, if nothing heats up, ramp up the voltage slightly.

[mgrharry]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

I did try injecting voltage there but even when ramping up to 2v 5a nothing gets particularly hot although coil PLS01 gets warm, along with several of the mosfets in that area but nothing is burning hot. Can't increase power more than that as the board only draws .88v when bench PSU maxes at 5a.

[DanielDacko]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

Ok, start removing mosfets one by one. Perhaps the board itself is shorted...

[mgrharry]

Re: Alienware Area 51M Monster Dual Jacks, 1 Shorted

I removed PSC01 and other caps but short still persists.