A common issue I’ve seen people run into with the HTC Vive Trackers is that they can’t track them without the controllers on. This is caused by a single line of code in the SteamVR_ControllerManager.cs file and is easy to change. All you need to do is find the section shown below and comment out the 2nd line there. As of the time this is written, that line # is 255 (it may change with steamvr updates).
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