Bluetooth is great. Except when it isn’t.
With the advent of Bluetooth Low Energy, iOS8 and OSX Yosemite, Macs and iDevices are intensively using Bluetooth to negotiate peer-to-peer connections (i.e. for AirDrop or Handoff). One major motivation to upgrade to an iPhone5s was compatibility with these features. AirDrop to my own phone can work, but it’s not reliable, as others have noted. I don’t like how it specifies person, not device. In this language, my MacBook and my iPhone are the same person so dropping from one to the other makes no sense. But it makes a lot of practical use. Myke Hurley has said on Connected that AirDrop ‘never works’ for him- I’m close to that point. It only has to fail a few times, before it becomes a non-feature. Instant Hotspot never worked for me.
But, worse, and increasingly regularly, I have problems with basic Bluetooth connections between a host (with user level interface) and a guest (with little or no user level interface). Here, negotiation can be confusing and difficult, and commits the host to be reliable. Yosemite brought increased reliability to my Retina Macbook’s Bluetooth, including the ability to hold connections to a larger range of third-party audio dongles.
However, again I saw the wonky line of “Bluetooth unavailable”. My Magic Mouse gives a double-green flash – which seems to be related to Bluetooth failure on the host. Magic mouse help has a lot of information on related problems. Incredibly, they found that “jerky” control can be temporarily fixed by a sleep-wake cycle. Oh come on!
The generic answer to Bluetooth connection/opreation problems is to reset PRAM (NVRAM, non-volatile RAM that stores system settings) and/or SMC (the system management controller). This process is not too painful. SMC reset seems to be more severe, and Apple seems to prefer if you didn’t do it. It shouldn’t help with Bluetooth. But I find that occasionally, it does.
For SMC reset, the laptop must be connected to power. On a 13in Retina Macbook, following shutdown, hold down the following four keys for a few seconds:
[left-shift, left-ctrl, left-alt (option) and the power button]
For PRAM reset, hold down ctrl-alt-P-R immediately after the startup chime, until a second chime is head (probably louder).
Every time that I had these problems, either the PRAM or SMC reset did the trick. Good, but the host is just not pulling it’s weight here.
My first question is – why is Bluetooth so unreliable in Yosemite, and getting corrupted off the PRAM and SMC, and why can’t OSX repair this problem automatically after detecting it?
My second question is – why cannot I not order these very efficacious reset commands from the “Bluetooth not available” icon – at least if I hold down the option key? Put an admin password gate on it. It would simplify recovery a great deal.