Richard wrote:
That's not quite true as written. The world *has* automotive lighting standards. Two of them: USA and ECE. Most of the world requires or accepts ECE-compliant automotive lighting and prohibits USA-compliant equipment; the US prohibits ECE and requires USA.
and parking lights and
Yes.
's and front marker lights
Yes, but there's a terminology problem here. What we are talking about in this thread as "city lights" or "parking lights" are properly called
*front position lamps* in ECE regulations and "parking lamps" in USA regulations. There is another function, properly called "parking lamps" in ECE regulations. This is the left-side-only / right-side-only front and rear lighting that can be switched on by the driver, as called for in the German road code (StVZO) when the vehicle is parked in certain kinds of streets after dark. ECE "parking lamps" are generally required to be white to the front and red to the rear, but may in some configurations be amber.the front and red in the
USA and ECE regulations both require red rear reflectors.
USA regulations have required amber front and red rear sidemarker lights _and_ reflectors on all vehicles since 1/1/70. In addition to improving side conspicuity by displaying the presence, position and direction of vehicles circulating in traffic after dark, the sidemarker reflectors serve the same function as the ECE "parking lamps" (i.e., provide parked-vehicle conspicuity in dark narrow roads). The US method is better in this case, for it is passive -- no action required by the driver to switch on -- and it consumes no power.
ECE regulations require sidemarker lights on vehicles over 6m long, and permit but don't require them on vehicles under 6m long. They are required to emit amber light, except that a vehicle's rearmost sidemarkers may emit red light if they are grouped, combined, or reciprocally incorporated with the taillamp, the rear end-outline marker lamp, the rear fog lamp, the brake lamp, or it is grouped or has part of the light emitting surface in common with the rear reflector. Most ECE-spec vehicles that have sidemarkers have amber front and rear ones. The new Citro=EBn C6 has amber front and rear sidemarkers even though the rear ones are built into the rear lamp cluster (and therefore could legally emit red light). But, many vehicles which in their US-spec configurations create the red rear sidemarker function by means of a wraparound red lens providing a "side view" of the bulb, likewise have the same setup in their ECE-spec configurations. Many BMW and Mercedes models have such a setup.
As for side retroreflectors: They are, as already mentioned, mandatory in the US on all vehicles. Amber front and intermediate, red rearmost. They are mandatory under ECE regulations on vehicles over 6m long, optional on vehicles under 6m long, and the ECE color requirement is amber, but the rearmost side retroreflector may be red if it is grouped or has part of the light emitting surface in common with the rear position lamp, the rear end-outline marker lamp, the rear fog lamp, the brake lamp or the red rearmost sidemarker lamp. Many vehicles which in their US-spec configurations have the red side retroreflector built into the side of the rear lamp cluster lens also have this configuration in their ECE models. Examples abound from BMW, Mercedes, Chrysler, Volvo and other makers.
mber rear turn signals > to make the vehicles look more American. BMW/Mini,= VW/Audi just don't care about providing this > safety feature to the drive= rs of North America.
I agree with you that amber rear turn signals are an utterly basic component of a proper automotive lighting system, and I agree with you that it's shameful to treat safety devices as stylistic toys, but having just returned the other day from a large automotive lighting technology congress in France, I can say you haven't got the whole story. I spoke with the BMW exterior lighting chief, and he told me they wanted to use the same type of amber rear signal on their US-market E90 3er as they use everywhere else in the world, but the US DOT objected. This type of "hidden" amber rear signal uses a clear bulb with a green plastic balloon over it, all behind a rose-red (dark pink) lens. The result is a lamp that looks red when off, but shines amber when on. It's subtractive color mixing. The technique has been in use for about 13 years or so -- no problem, such signals work fine and don't notably degrade with age or use. But, the DOT said the green plastic for the balloon was not on the list of approved plastic materials for use in car lights, and they kept saying "no!" or simply stalling and not answering at all regardless of how much test data BMW submitted. Finally DOT said "OK", but by then it was too late; in order to meet production schedules, BMW had to make an alternate choice for the US market. They could've gone to a plain amber lens, or a clear lens with amber bulb, but for whatever reason (probably related to tooling cost), the red lens was their emergency "Plan B". This is the same reason why the first-year Audi A8 had these green-ballon/pink-lens/amber-light rear turn signals, but subsequent years had red lenses: DOT bitched about the green balloons being made out of an unapproved plastic.
The situation is different with Audi: On some of their present car designs, they couldn't have an amber rear turn signal without the red brake/tail lamps being too small to comply with US surface area requirements, so the only choices were to redesign the rear lamps entirely (larger - not approved by the stylists) or have a red rear turn signal for the North American market. This is the same reason why older BMW 5er wagons had red rear turn signals. Other Audi models have plenty of rear lamp area to have an amber turn signal, but as Audi's chief of exterior lighting explained, "if some of your vehicles have red and some have amber, this does not look like a coherent line of vehicles. I don't like red rear signals, but they're just as legal as amber in North America."
I didn't get a chance to ask about the MINI's red rear signals; that's neither a materials nor a surface area problem.
Honda, Toyota and Subaru are actually markedly *worse*, together with Ford, GM and Chrysler: All their models have rear lamp designs with ample area for amber rear signals, and they don't tend to use materials that DOT gets itchy about -- they use red signals in North America for specious "customer preference" reasons (have you ever been asked to vote?) or because red ones are cheaper to make and "show us the pile of dead bodies indicating that amber is better!".
here in North America.
No, they aren't. They play with it, back and forth, red to amber and back to red, as a stylistic toy. The newest Jeeps all have red, after many years of using amber, for instance.
Red ones would be almost marginally tolerable if they were all the combination brake/turn type, but immediately-adjacent, colorimetrically- and photometrically-identical separate red brake and turn lights duelling with each other make it very difficult to acquire the vehicle's signalling messages quickly and accurately in traffic. It's known that following drivers react significantly more quickly and accurately to a vehicles *brake* lamps if the vehicle's turn signals are amber rather than red, but nobody's bothered doing a study in actual traffic, so while all the regulators know red ones are dumb and amber ones are good, the automakers' lobbyists prevent legislating for amber rear signals in North America. "Show us the pile of dead bodies!" (the Ford guy actually said "It's the only light that flashes on the back of the car, why does it need to be a different color?".)
DS