Hello, I have also have a similar issue. I have two different Lidarlite v3s (both have 2019 label as shown in picture above) and two different pixhawk 4s (tested firmware 1.8 and 1.9) and have tested them both similarly in the console. If I repeatedly do a “ll40ls start i2c” over and over again I can eventually get the ll40ls driver to start. Sometimes it takes 10 times or more. (I figured this out by accident as it just started for me once randomly, and after repetitive testing it started again)
Has anyone else seen this issue, or have a solution?
Other things to note: Tired with both powering the lidar from the I2C buts and from external power supply, tried both with capacitor and without, have never seen it start successfully on PX4 boot