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Interpretation ID: 86-5.34

TYPE: INTERPRETATION-NHTSA

DATE: 10/24/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Mr. H. Tsujishita

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your letter of July 15, 1986, asking three interpretation questions concerning Federal Motor Vehicle Safety Standards Nos. 101, Controls and Displays, and 108, Lamps, Reflective Devices, and Associated Equipment. The answers to your questions are provided below.

By way of background information, the National Highway Traffic Safety Administration does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of the manufacturer to ensure that its motor vehicles or equipment comply with applicable standards. The following represents our opinion based on the information provided in your letter.

Your first question concerns the visibility requirements for the upper beam telltale (indicator). As noted by your letter, section S5.3.3 of Standard No. 101 provides that the light intensity of each telltale shall be such that, when activated, that telltale and its identification are visible to the driver under all daytime and nighttime conditions. The upper beam telltale is one of the telltales subject to that requirement. You note, however, that section S4.5.2 of Standard No. 108 requires a high beam indicator that conforms to SAE Recommended Practice J564a (except that the signal color need not be red). J564a provides that the upper beam indicator should be "plainly visible to drivers of all heights under normal driving conditions when headlights are required." Based on this provision, you suggest that the upper beam telltale is not required to be visible to the driver under the daytime conditions when headlamps are not needed. As discussed below, your understanding is incorrect.

The difference between these two requirements is not so great as you suggest. The reference to "normal driving conditions" in J564a includes a variety of non-nighttime conditions (e.g., driving at dusk or dawn, and driving in daytime rainstorms) when headlamp use may be required by the States. To the extent that Standard No. 101 requires the telltale to be visible under daylight driving conditions not covered by Standard No. 108, manufacturers must meet the broader requirement. Manufacturers are required to meet all applicable safety standards. We note that while Standards Nos. 101 and 108 each cover upper beam telltales and specify different requirements, it is possible to meet the requirements of both standards simultaneously.

You stated that under daylight conditions the upper beam cannot dazzle oncoming drivers and that there is therefore no need to inform the driver that the upper beam is on. While there may be less need for this telltale during daylight than at night, Standard No. 101 reflects our belief that there is still a need and requires that the telltale be visible under all daytime and nighttime conditions (if the upper beams are actually on).

Your second question concerns the upper beam telltale minimum area requirement. SAE Recommended Practice J564a, which, as noted above, is referenced by section S4.5.2 of Standard No. 108, provides that the upper beam indicator should consist of a "light, with a minimum area equivalent to that of a 3/16 in. diameter circle." You asked how this requirement would apply to two designs.

In the first design, the outline of the telltale symbol would lighten while the area within and around the telltale symbol would not. You suggested that the framed area, i.e., the area within the telltale that is framed by the outline but not lighted itself, can be counted into the minimum area requirement. As discussed below, that is incorrect. In the second design, the telltale symbol would be superimposed on a rectangle. In this case, the entire area within the rectangle would lighten, except for that covered by the symbol itself. You suggested that the lighted area other than that covered by the symbol can be counted toward the minimum area requirement. As discussed below, that is correct.

In referencing SAE Recommended Practice J564a, Standard No. 108 requires that the upper beam indicator must consist of a light, and also specifies the minimum area for that light. It does not specify the shape of the light. If the light is a simple circle which is lighted in its entirety (with the identification required by Standard No. 101 placed adjacent to the circle), that lighted circle must be at least 3/16 inch in diameter. If the light is some other shape, such as the shape of the upper beam symbol or a rectangle in which only part of the area is lighted, the total area which is lighted must be at least as large as the area of a 3/16 inch circle. Thus, in the case of the first design discussed above, only the outline area (i.e., the blue lighted area) of the upper beam symbol can be counted toward the minimum area requirement. The unlighted interior part (i.e., the black area) of the symbol cannot be counted toward the minimum area requirement. In the case of the second design discussed above, the entire (blue) area within the rectangle that lightens can be counted toward the minimum area requirement. However, that part of the rectangle which does not lighten, i.e., the (white) part covered by the symbol, cannot be counted.

Your third question concerns Standard No. 101's illumination requirements for a side marker lamp control that is incorporated into the master lighting switch. As suggested by your letter and as discussed below, illumination is not required if the identifying symbol for the side marker lamps is marked on the master lighting switch.

While Table 1 of Standard No. 101 requires that side marker lamp controls be identified with the side marker lamp control symbol and that such identification be illuminated, it also provides that separate identification is not required if controlled by the master lighting switch. Thus, for side marker lamp controls that are incorporated into the master lighting switch, use of the side maker lamp control symbol is voluntary. Since such identification is not required by Standard No. 101, it is our opinion that the standard does not require manufacturers to illuminate such identification if they choose to provide it voluntarily.

SINCERELY,

AGENDA 4-b DAIHATSU MOTOR CO., LTD.

Erika Z. Jones Chief Counsel Office of the Chief Counsel National Highway Traffic Safety Administration

Dear Ms. Jones:

Additionally to the questions which we sent by letter date Feb. 18, 1986, would you please kindly answer the questions with regard to the interpretation of FMVSS Nos. 101 and 108 as described on the following pages?

H. Tsujishita Chief Co-ordinator of Technical Administration Dept. Head Office

ENC.

1. FMVSS Nos. 108 & 101; Highbeam Indicator Visibility requirement

Paragraph S5.3.3 of FMVSS No. 101 provides that each tell-tale and its identification shall be visible to the driver under all daytime and night time conditions. According to this provision, highbeam tell-tale shall be visible even under daytime condition.

On the other hand, paragraph S4.5.2. of FMVSS No. 108 requires a highbeam indicator which conforms to SAE J564a on each vehicle, and SAE J564a provides that the highbeam indicator shall be plainly visible to the driver under normal driving conditions when head lights are required. That means, under daytime conditions whenhead lights are not required, the highbeam indicator is not needed to be plainly visible.

We believe that the purpose of the highbeam indicator is essentially to indicate the driver that the upper beam of the head lamps are on to prevent the opposite driver from being dazzled by passing each other with the upper beam on. Under the daytime condition, as the upper beam can not dazzle the opposite driver any longer, and there is no need to indicate the driver trat the upper beam is on.

Therefore we believe that the high beam indicator (tell-tale) is not required to be visible to the driver under the daytime conditions when head lights are not needed.

Is our understanding right?

2. FMVSS No. 108; Highbeam Indicator Minimum Area Requirement

As stated above, S4.5.2 of FMVSS No. 108 requires a highbeam indicator which conforms to SAE J564a on each vehicle, and SAE J564a provides that the highbeam indicator shall have a minimum area equivalent to that of a 3/16 in. diameter circle.

A. In case that only the frame of the tell-tale will be lighten

We believe the framed area can be counted into the minimum area requirement.

B. In case that the background of the tell-tale will be lighten

We believe the entire shaded area can be counted into the minimum area requirement.

If our understanding is wrong, please explain in the above requirement in detail.

(Graphics omitted)

3. FMVSS No. 101; Side Marker Lamp Control Illumination

Table 1 of FMVSS No. 101 requires that the identification of side marker lamp control shall be illuminated when the head lamps are on, and it also provides in its footnote that separate identification (for the side marker lamp control) are not required if the side marker lamp are controlled by the master lighting switch. In case that the side marker lamps are are controlled by the master lighting switch and the identifing symbol for the side marker lamps is marked on the switch voluntarily by the manufacturer, we believe that the illumination for the side marker lamp control is not required, because the side marker lamp control which is combined into the master lighting switch is easily identifiable.

Is our understanding right?