Zwift Thinks IMac Bluetooth is Off


I’m getting a message stating my Bluetooth is switched off on my late 2009 Apple IMac. I’ve carried out the Bluetooth reset and it seems fine with mouse & keypad connecting but when I open Zwift I’m still getting the warning triangle stating Bluetooth must be off.

Zwift updated so I’m assuming it’s not a software update issue.

Any suggestions would be greatly appreciated, thank you.

I run Zwift on a mid-2010 iMac running OSX Sierra. In my case (and perhaps yours too), the onboard Bluetooth adapter is not Bluetooth 4.0 compatible so Zwift won’t detect it. My solution was to run everything via ANT+ using a USB adapter and extension cable.

For curiosity’s sake, last week I bought a cheap USB Bluetooth 4.0 adapter off Amazon and stuck it into my iMac. I got the iMac to use the adapter using the following command:

sudo nvram bluetoothHostControllerSwitchBehavior=always

Following a reboot of the computer I could get the iMac to detect everything (trainer and HRM) via the Bluetooth adapter.

However, ANT+ is much more reliable for me so I’m sticking to that.

Thanks Adrian that is great to know. I’ve just ordered a Ant+ dongle & extension as I realised my Garmin Run HRM is Ant+

Adrian did you have any issues with the wireless mouse & keyboard picking up the new BT dongle ?

Not really, the BT mouse and keyboard paired on the 1st and 2nd attempt respectively. I had a wired mouse and keyboard plugged into the computer throughout the process though.

I have a 2011 iMac, OSX High Sierra 10.13.6, with the built in Bluetooth that you mention is not compatible with the 4.0 requirements for Zwift. Most USB 4.0 adapters do not seem to be Mac compatible - any recommendation as to brand of the cheap USB that you bought ?

I have an IOGEAR GBU521 4.0 USB (and one by Hideez), but neither seem to work on the iMac. I can plug them in and have tried the SwitchBehavior command and also the Xcode HCI selector method to ensure the adapter is used, but the adapters simply do not connect to the magic mouse (or wireless keyboard). I think they are Windows compatible only maybe.

Rob, did you try running the sudo command that I listed above? That should default the mac to looking for an external BT adapter first, rather than always defaulting to the inbuilt one.