Separate the terms
A description of the light technology and a description of an assistance function answer different questions. Automatic switching, high-beam assistance and adaptive lighting should not be assumed merely from the shape of a lamp or the presence of an LED description.
Ask what the car actually does
Have the seller explain the claimed feature in practical terms and locate its controls or settings. Compare the wording with the specific vehicle's instructions. Avoid relying on a demonstration from a different model, even when the lamp design looks similar.
Inspect safely while parked
Check visible lamp condition and ask the seller to operate ordinary lighting controls where it is safe to do so. Do not stare into bright lamps, disassemble a lighting unit or improvise a road test to provoke an assistance function. Some functions cannot be meaningfully evaluated in a stationary daylight viewing.
Record the limits of the check
Separate a visual check from confirmation that every lighting function works correctly. If lamps have been replaced, ask what work was done. Have questions about alignment, compatibility or warning messages assessed by a qualified workshop. In a comparison sheet, use clear entries such as lighting type described, basic lights demonstrated and adaptive function not tested rather than a single unchecked premium lighting claim.