Apple Service Diagnostic 3S138

Software Apple Service Diagnostics (ASD) is distributed to service providers for repair and maintenance products Apple. Annex Apple Service Diagnostics is designed to run EFI and Mac OS X tests from external USB-carriers. Apple Service Diagnostics (EFI) performs direct low-level tests of hardware for Apple computers and requires no operating system, while Apple Service Diagnostics (OS) uses Mac OS X to run these tests.