The TS4231 must be configured for optimal light detection. The communication interface to the TS4231 is a two-wire interface that connects to the E/D pins of the device. When the device is connected to the SteamVR Tracking HDK, the HDK performs the configuration of the device.
For applications that do not use the HDK, Triad has provided an Arduino library that can be used to configure the TS4231. The library can be found inside the Arduino library manager or downloaded from Github here: