Symptom
Apple Hardware Test (AHT) may state that the Bluetooth module is not present when it actually is present.
Solution
To verify presence of the module:
1. Restart the computer from the hard disk.
2. Open Apple System Profiler (/Applications/Utilities/).
3. Click the Devices and Volume tab.
4. Look to see if the Bluetooth module appears on the USB bus (Figure 1).
Figure 1 Apple System Profiler