15″ Macbook Pro Water Damage

Totally dead Macbook Pro 15″.

Left; This is test of original capacitor from lower right of IC.

Right; Final repair of area with new TPS5115 IC in place, new capacitors, conformal coat and corona dope treatment. Capacitor on left has new voltage rail wired-in, a re-route from the damaged area of board that had shorted out, burned to a char. I removed all of this charred board at this site until short was gone.

This capacitor did not stand up to scrutiny.

Carved-out charred board – freed of shorting layers, now saturated with corona dope and covered in conformal coat.

Removing IC and testing capacitors…

Before I remove the IC – I know I have to fight the OEM ROHS no-lead solder. That kind of solder turns into concrete on shorted component joints. It doesn’t melt! I mask heat from near-by plastic connector with aluminum tape and kapton tape. I preheat entire board. I flow either leaded solder or low-melt (roses metal) onto all connections of IC with my soldering iron. Now I remove chip with my hot-air rework station.

Left; prep for chip removal.

Right; 6.63uF – not 10uF, with that ESR – that’s a bad capacitor!

Preparing to remove TPS51125 IC chip that glowed in thermal image.

One of the capacitors by the hole burned in the board by hot area looked suspicious – it should have been 10uF – it is not…however it’s ESR is not suspect, leakage not the issue.

Left; Chip and caps removed. Oh dear. oh…

Right; Let’s clean up everything, get a full appreciation of the damage…

IC removed…

IC and capacitors removed, there’s a HOLE in the board! this point was hot, shorted…I cleaned all up to see what I have left to work with, how much rework is required…

Notice pin hole burned through lower right of the original chip

Left; Thermal image of the TPS51125 IC chip that creates the 3.3V and 5V rails for the entire board. It’s shorted, burning hot.

Right; See hole in board between the two capacitors? Chip was shorting to ground inside the board, between layers. I had to carve out all this charred board and planes. Roasted glas fibre epoxy and copper foil layers.