I recall Fanaleds application was claiming to support the LEDs,I tried once,did not work so I gave up quickly as it wasn't too important for me. Try your luck and report back for success or failure: https://www.fanaleds.com/
Fanaleds works fine with LFS (and default cars). But you need to configure each car first! Out of the box Fanaleds shows only leds (blinking) if pit limiter is on. In any other case without configure the cars nothing will shown.
Since LFS with mod support the mod car names are wrong detected (but work also). I've reported that to one of the developer. Hope he find time to fix that issue. But perhaps a donation will "push" such fixes, too?