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Hi, I replaced the battery with a new battery from ifixit and got a new 85W magsafe adapter from Best Buy. After replacing the battery the laptop would boot fine and would stay charged as long as it was plugged into the wall. The battery is now completely discharged. In order to boot the laptop I have to do the following: Disconnect the power adapterHold the power button for 10 secondsWhile holding the power button reconnect the power adapterContinue to hold the power button for another 10 secondsWhen the power button is released the computer boots and chimes What are the next troubleshooting steps I can take from here?
The procedure you’re using there is a boot in SMC bypass mode. If the Mac doesn’t boot in any other way it means you have a faulty SMC circuit or IC. It’s not an easy troubleshooting though, since SMC gets and supplies data to a very large number of components..you’ll need schematics, boardview and at least a multimeter to start with.
