HID headlamp upgrades likely fail new MOT rules Classic cars fitted with HID bulbs without the necessary upgraded bulb fittings will fail an MOT test under new rules coming in during May 2018. This is the lead item in this weeks issue of Classic Car Weekly. Regulatory position on the use of LEDs in historic vehicles See also our NEWS item issued in October 2017 following an update from Ian Edmonds on the use of LEDs in vehicles in the UK. More Posted: 180315 Classic cars fitted with HID bulbs without the necessary upgraded bulb fittings will fail an MOT test under new rules coming in during May 2018. Using HID (high intensity discharge) bulbs has been an upgrade some owners of classic cars have used to increase the brightness of their headlamps as the kits are readily available at a relatively low cost. But this modification does not meet the the safety requirements of the new MOT test unless the fitting and reflector are suitable for the HID bulb. According to the MOT tester manual it is not permitted to convert existing halogen headlamp units for use with HID bulbs after 20th May 2018. Classics can use HID bulbs but they have to be part of an entire unit designed for HID bulbs which incorporates a headlamp self levelling system to avoid dazzle. The FBHVC says "this is a recent addition to the MOT inspection manual but is entirely consistent with previously published DfT advice. The reasoning is sound and based on the high probability that an HID light source in a lamp fitting not designed for an HID will produce glare and dazzle". Other reports indicate dazzle has become an increasing factor in road accidents so on safety grounds an MOT failure for a car with an HID upgrade in a light fitting designed for a halogen bulb is welcome. With the MOT exemption concession available for cars over 40 years old from 20th May 2018 it is likely that some cars, where an HID upgrade has been made to a car that is no longer subject to an annual MOT test, will not be picked up. Those enthusiasts who choose to not have an "MOT exempt VHI (Vehicle of Historic Interest)" car subjected to a voluntary MOT test or inspection will need to act responsibly and check whether their headlights have an HID upgrade and if so then either fit the correct unit designed for an HID installation or remove the HID upgrade and revert to halogen bulbs.