What is the white wire on my Smartphone Controlled Underbody Box?

The white wire on the Smartphone Controlled Underbody Box is for the courtesy feature. The white wire would connect to the dome light or door pin trigger of the vehicle. Whenever the car door is opened the courtesy lights will turn on your underbody, wheel well, and interior lights to a solid white. For additional information please refer to page 8 of the installation guide. 

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