ANT+ Sensor Dropped Due to Laptop Power Mode Change

Just a heads up in case someone else has the same issue as I encountered.

Issue: Noticed my ANT+ sensor connected to my laptop cut out when the power mode of my laptop changed from Normal to Battery Saving. I couldn’t get the ANT+ sensor to come back online until I restarted Zwift. My laptop wasn’t plugged into the power bar.

I restarted Zwift and everything was working as usual. As I was running out of batteries, my wife helped me plug in the laptop and all of a sudden, same issue, the ANT+ sensor dropped out. So my laptop must have some affect on the ANT+ sensor either way.

Workaround: Have your laptop plugged in before you start. Or have your laptop stay in one power mode. I normally have my laptop plugged in before I start Zwift, but yday was an exception (due to laziness). I may run a few more scenarios to rule out Zwift as the issue (by using another program). 

Hi Mike,

Please also see this from

"Make sure your machine is not trying to power down the USB ports to put them into “low-power” mode. This is more common on Windows when running in “Battery Optimized” power profiles, but is also true on Apple MacBook style laptops when the battery dips below 10%.

  1. To check this, go into Device Manager, and at the bottom will be your USB ports and devices.
  2. Expand that section and look for “USB Root Hub” or something similar that represents the onboard USB ports of your machine, or the ports of the device you plug your ANT+ adapter into.
  3. Right-click on the device and choose “Properties”
  4. Choose the “Power Management” tab on the far right. Inside that tab, will be any power management-related capabilities of that USB device. In my case, my desktop PC’s USB ports were set to go into low-power mode, despite my machine being a non-laptop gaming machine and configured with the “High Performance” power management profile.
  5. Uncheck any options that try to put your USB devices into low-power mode from this dialog."
1 Like

I have a similar type issue in that I have my computer, tv, turbo & fan plugged into an extension bar. However rather randomly if I turn the lights on in the garage I hear the usual sound of a device being removed from the USB ports. It then does the noise of it being plugged back in but if I’m in shift at the time the ant+ drops everything until I quit zwift completely. Just awaiting the arrival of a surge protector to see if that keeps things stable

David, thanks for the suggestion. I will try disabling any settings that try to manage USB devices.


Stuart, that definitely sounds like a situation where your laptop may be experiencing power variations and may be causing the system to think that there are power changes. See if David’s suggestion helps first.