820-01987 no power

[Kyle93]

Arrived with liquid damage on trackpad connector and a few capacitors. Pads 50-44 and 49-43 are completely gone on trackpad connector. PPBUS_G3H is shorted.

Only 3-4ohms resistance to ground on two of the large CPU coils.

What should be tried next? Using 820-01598 boardview as a reference, cant find 820-01987 boardview

 

[2informaticos]

Probably the short is caused by trackpad connector, remove it.
Also compare resistance to ground with all big coils, just in case.

 

[Kyle93]

short is still there after trackpad connector removed,

resistance to ground on big coils is different then PPBUS_G3H resistance to ground. PPBUS_G3H 1.8ohms. CPU big coils 3.9ohms. All other big coils are much higher

 

[2informaticos]

Then is safe to inject voltage.
Start with low voltage as 1V, and increase maintaining the current under amp limit.

 

[Kyle93]

Injected voltage and only area that gets warm is the trackpad area. Did some scrapping but short still remains.

Does This look like a hopeless repair?

 

[2informaticos]

Probably short between copper layers.
Use fiberglass pen to clean that area.