Some owners have switched out the older style HID headlights with the later LED headlights. The very latest S/X headlights use a matrix LED design and these headlights can NOT be used. You will need the LED headlights used in cars from the 2016-2020 era. (Jan-2023)
In addition to replacing the headlight assemblies and adding the Headlight leveling ECUs, one additional data line (LIN) is required for each headlight that is not in your wiring harness. These wires are routed from the headlight through the firewall into the cabin to the BCM (Body Controller Module). This is not a high current line, so using 20-22 AWG wires will be fine.
The BCM connector X021 pin 19 connects to:
- The left headlight connector x261 pin 1, and
- The left headlight leveling ECU connector x267 pin 3
The BCM connector X022 pin 11 connects to:
- The right headlight connector x261 pin 1, and
- The left headlight leveling ECU connector x261 pin 1
Once the new LED headlights are installed, you will need to use Toolbox 3 to upgrade the BCM module to support LED headlights.
Note: We have not done this project ourselves, and are reporting what others have done. There may be other connections required to make these work. One owner didn’t bother with the Headlight leveling ECUs and had the headlights working, but it’s unclear if they can be leveled without the leveling ECU functioning.