MacBook Air computers have a built-in, diagnostic LED. Observe the power light located on the front of the computer and note the flash patterns.
If the diagnostic LED displays five flashes upon startup, and the pattern repeats after a brief pause, the computer's battery may require service. If the power adapter is present and connected to a working power source, the MacBook Air will continue to start up normally; however, the battery should be diagnosed and replaced if necessary.
This 5-flash LED pattern may also occur when waking the computer from sleep if the power adapter is connected and the battery requires service. This is intended to let you know that the battery requires service but can still accommodate continued operation until it can be replaced.
Important: It is important to note that the "Safe Sleep" function may be unable to recover unsaved data if the MacBook Air's power is interrupted during operation while in this state.
Note: If you've replaced the system battery, it may take up to 10 minutes to verify the repair using the LED diagnostic on POST. After replacement, the battery should be charged for at least 10 minutes. This brief burn-in period is recommended to ensure that the new battery has enough power to operate correctly.
Note: To learn about other Power-On, Self-Test diagnostic beeps and LED patterns, see Kbase articles 58183 and 58442. To learn more about the Intel-based Mac startup sequence and error codes, see Kbase article 303083.
Was this article helpful?