Another dead Macbook Retina with SMC issues
We have got another Macbook Retina which out of the blue decided not to turn on one morning. After measuring all the voltage rails, we have noticed that S3 rails were not present.
Macbooks pass through couple stages before they turn on. S5 state is when they receive power and expecting power button to be pressed.
Next stage is the S3 state, where when the power button is pressed or the charger is connected with the detached keyboard the SMC collects all power good signals from different chips in the system and sends PM_SLP_S4_L as one of the output signals to tell the system to transition from S5 (shut down) to S3 (sleep) and following S0 (turned on) states.
Initially, we have checked all responsible voltages to the SMC and all were fine. However, the SMC still were not producing the signal.
Macbook Repair in Adelaide includes a couple of simple steps:
- Quote for the repair before any work is done, even over the phone.
- Free pick up from the client’s location in Adelaide. Or alternatively, drop in for a quick check while you wait.
- Confirming final cost and “Go” from the client.
- Repairing and ensuring everything works as expected.
- Returning repaired system back to the client. Or the client can pick it up from our workshop.
We pulled the board out of the Macbook and start investigating under a microscope. There was no apparent liquid damage on the system, so the only explanation was either the SMC collected some oxidation underneath or some of the connections were not making good contact.
Macbook SMC chips are BGA chips and are soldered to the logic board. They also keep proprietary code which cannot be easily flashed into a new blank chip. So replacing the SMC chip is not the first choice here.
Looking at the Macbook we could see that it was overheating heavily. It was dusty inside and even the thermal compound on the heatsink was completely dry. It should be fresh with a consistency of toothpaste.
We start looking at the possibility of SMC having cold joint and we knew that we had to reflow the SMC to be able to repair this Macbook.
We have sophisticated equipment in our workshop with a high accuracy microscope, ultrasonic cleaning bath, reflow machine, and micro-soldering tools to achieve high-quality logic board repairs. With hundreds of components in stock, we can quickly locate and replace faulty chips, resistors, and capacitors in Macbooks.
Reflow procedure basically resolders the chip and with the help of flux, it pushes out any gunk which may have collected underneath.
The last step was to run the board through an ultrasonic cleaner. This way we ensure that the logic board gets rid of all the unwanted dirt and oxidation around and underneath the components.
After assembling the Macbook, all worked fine and we let it run tests overnight before customer picked it up.
In case you have a Macbook which is not behaving as expected and need a repair always rely on professionals, These are expensive computers and small mistake may cause you a fortune. Apple electronics are extremely sensitive to ESD and any mishandling may result in damaged logic board.