discool
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The dim-dip systems were not intended for daytime use as Daylight Running Lamps DRLs. Rather, they operated if the engine was running and the driver switched on the parking lamps (called "sidelights" in the UK). Dim-dip was intended to provide a night time "town beam" with intensity between that of the parking lamps commonly used at the time by British drivers in city traffic after dark, and dipped (low) beams; the former were considered insufficiently intense to provide improved conspicuity in conditions requiring it, while the latter were considered too glaring for safe use in built-up areas. The UK was the only country to require such dim-dip systems, though vehicles so equipped were sold in other Commonwealth countries with left-hand traffic.
In 1988, the European Commission successfully prosecuted the UK government in the European Court of Justice, arguing that the UK requirement for dim-dip was illegal under EC directives prohibiting member states from enacting vehicle lighting requirements not contained in pan-European EC directives. As a result, the UK requirement for dim-dip was quashed.
Nevertheless, dim-dip systems remain permitted, and while such systems are not presently as common as they once were, dim-dip functionality was fitted on many new cars well into the 1990s.
The dim-dip systems were not intended for daytime use as Daylight Running Lamps DRLs. Rather, they operated if the engine was running and the driver switched on the parking lamps (called "sidelights" in the UK). Dim-dip was intended to provide a night time "town beam" with intensity between that of the parking lamps commonly used at the time by British drivers in city traffic after dark, and dipped (low) beams; the former were considered insufficiently intense to provide improved conspicuity in conditions requiring it, while the latter were considered too glaring for safe use in built-up areas. The UK was the only country to require such dim-dip systems, though vehicles so equipped were sold in other Commonwealth countries with left-hand traffic.
In 1988, the European Commission successfully prosecuted the UK government in the European Court of Justice, arguing that the UK requirement for dim-dip was illegal under EC directives prohibiting member states from enacting vehicle lighting requirements not contained in pan-European EC directives. As a result, the UK requirement for dim-dip was quashed.
Nevertheless, dim-dip systems remain permitted, and while such systems are not presently as common as they once were, dim-dip functionality was fitted on many new cars well into the 1990s.
