حساس المسافة الأمامي معيب

The forward-looking radar or lidar unit that measures distance and closing speed to the vehicle ahead, feeding adaptive cruise control and forward collision systems. A fault here disables driver assistance functions rather than affecting how the vehicle drives, and the systems are designed to withdraw cleanly and tell the driver — which is the correct behaviour and not itself a defect.

Most faults are not electronic. The unit looks through the grille or the screen, so anything in that path degrades it: packed snow or ice, mud, a bug-covered radome, an aftermarket badge or number plate surround, or accident repair that has moved it. Alignment is the commonest genuine fault — a sensor a fraction of a degree out aims at the wrong lane, which produces erratic behaviour rather than a clean failure, and it must be recalibrated after any front-end work.

Where several sensors are fitted, the codes name which, distinguishing a single centre unit from left and right corner units, and reading one as another sends the work to the wrong side of the vehicle. Rule out obstruction and alignment before replacing anything, and expect that a replacement will need calibrating to the vehicle before the systems will re-enable.