A Mac that keeps shutting down or restarting can be frustrating, especially when it looks like the problem has no clear cause. In our case, a MacBook that had been unused for months would power on, run for a few minutes, and then shut down again. The fix was simple: resetting NVRAM/PRAM and SMC resolved the issue and brought the Mac back to normal.
What was happening
The Mac started normally, but after a few minutes it would auto-shutdown consistently. That kind of behavior can happen when power-management settings become confused, startup values get stuck, or the system controller stops behaving correctly. On Intel Macs, NVRAM/PRAM stores selected startup settings, while the SMC handles power, battery, thermal, and sleep-related functions.
Why these resets help
NVRAM/PRAM can store settings related to startup disk selection, display behavior, and other low-level preferences. Resetting it can clear strange startup behavior or hardware-related configuration issues. The SMC is especially important on Intel Macs because it manages power delivery and related system behavior, so resetting it can help when a Mac shuts down unexpectedly or behaves as if the power system is unstable.
Before you begin
- Before resetting anything, try these quick checks:
- Disconnect unnecessary accessories.
- Make sure the charger and cable are working.
- Save your work if the Mac is still usable.
- Shut the Mac down completely before starting.
Reset NVRAM/PRAM
Intel Macs
- Shut down the Mac.
- Turn it on and immediately press and hold Option + Command + P + R.
- Keep holding the keys for about 20 seconds.
- Release them and let the Mac continue starting normally.
Apple Silicon Macs
Apple silicon Macs do not use the same manual NVRAM/PRAM reset process as Intel Macs. In most cases, shutting the Mac down and starting it back up is enough for basic troubleshooting because the startup system is handled differently
Reset SMC
Intel MacBook with built-in battery
- Shut down the Mac.
- On the built-in keyboard, press and hold Shift + Control + Option on the left side.
- While holding those keys, press and hold the power button.
- Hold all four keys for 10 seconds.
- Release everything, then press the power button again to turn the Mac on.
Apple Silicon Macs
Apple silicon Macs do not have the same traditional SMC reset procedure as Intel Macs. If the Mac is acting up, shut it down completely, wait a short time, and power it back on.
What happened after the reset
After resetting NVRAM/PRAM and SMC, the Mac stopped shutting down unexpectedly. It could boot normally, stay on, and work without repeating the same power problem. That strongly suggested the issue was related to stored configuration or power-management behavior rather than a permanent hardware fault.
When this may not be enough
If the Mac still shuts down after these steps, the problem may be a weak battery, faulty charger, overheating, or a logic board issue. Apple recommends checking power connections and using Apple Diagnostics if the issue continues. On older Intel MacBooks, battery health is especially important because a degraded battery can cause sudden shutdowns under load.