My headlights are dazzling other drivers
QOther drivers frequently flash me even though my 1980 Mini’s headlamps are on dipped beam. Why might I be dazzling them, and what can I do about it?
Julie Greenwell, Dungeness
Martin says:
AStand in front of the car with the dipped beam on. Bend down until you can see just the upper part of the reflector illuminated with an almosthorizontal cutoff. If the whole reflector is illuminated, then the bulbs may be wired incorrectly (flick the dipswitch to check). Alternatively, if one random part is illuminated, the bulbs are wrongly-installed. Sometimes H4 bulbs with a three-point base are used instead of tungsten bulbs with a round base. In this case, the filament ends up in the wrong place and the light cannot be correctly focused.
You can buy round-base halogen conversion bulbs, so there’s no excuse for this. Cheap LED and HID ‘upgrade’ kits are also notorious for bad focus and can be a real menace.
If all seems in order then the headlamp aim is probably incorrect. Drive up to a wall on level ground, mark the headlight centres, then reverse about 5 metres. On full beam, the bright ‘hot spot’ should be around this cross – not higher and not to the right of it. On dipped beam, there should be a cutoff between bright and dark about 50mm below the cross. On older headlamps, this is a bit less distinct. On newer types with asymmetric beams, it should be sharp, with a triangular kick-up of light to the left only. The kick-up should start just to the left of the cross.
Some times a defective bulb can cause a strange beam pattern. If the pattern is correct but in the wrong place, use the vertical and horizontal adjusting screws on the headlight to adjust the beam position. On your Mini, the screws are behind the headlamp bezel (see manual) but on more modern classics they’re usually in the engine bay, on the back of the headlamp unit.