If you're testing the battery for a Tesla Model 3 / Model Y, the area to plug in the Lyteflo Device is located in the behind a plastic cover at the bottom rear side of the center console.

To give yourself more space, you can slide the front seats forward and when you're ready, hop in the back seat.

You can use the plastic "Flobar" provided in your Battery Kit to pry off this trim piece and you may want to wrap the end of the Flobar in a cloth to protect the trim from scratches.

Walkthrough Video: How to plug in Lyteflo device & get a Battery Report on Tesla Model 3 / Model Y (2019-2024) 🔋

Here's a video showing how to plug in the device and generate a report for Tesla Model 3 & Model Y (2019-2024):