If wired correctly (did you get the original Land Rover wiring loom?) the relay feeds the lights from the battery and it's only switched by the BECM (small load).
This is the way it should be done and the original loom works this way, so no risk of BECM damage.
Sigi
This is the way it should be done and the original loom works this way, so no risk of BECM damage.
Sigi