Apple Service Diagnostic ASD 3s140



Apple Service Diagnostics (ASD) is distributed to Apple Service Providers. The Apple Service Diagnostics application is designed to run both EFI and Mac OS X tests from an external USB hard drive. Apple Service Diagnostics (EFI) runs low-level tests of the hardware directly and does not require Mac OS X, while Apple Service Diagnostics (OS) uses Mac OS X to run tests.