Interpretation ID: nht91-4.37

DATE: July 3, 1991

FROM: Michael D. Incorvaia -- Manufacturing Engineering Manager, Wagner Lighting

TO: NHTSA -- Office of Chief Counsel

TITLE: Re Request for Letter of Interpretation

ATTACHMT: Attached to letter dated 11-12-91 from Paul Jackson Rice to Michael D. Incorvaia (A38; Std. 108)

TEXT:

Wagner Lighting is requesting an interpretation on Federal Motor Vehicle Safety Standard (FMVSS) 108 per the documentation that follows.

All responses by NHTSA to this request should be addressed to:

Michael D. Incorvaia Manufacturing Engineering Manager Wagner Lighting P.O. Box 4650 Sevierville, TN 37864.

Wagner Lighting, a manufacturer of automotive and truck turn signal and hazard warning flashers for more than thirty years, requests a letter of interpretation from NHTSA concerning FMVSS 108. Per 49 CFR 512 4b3i, Wagner Lighting wishes to keep this request confidential because this concept is a trade secret.

Per 512 4b3ii and 4b3iii, Wagner Lighting has disclosed this information to three (3) sources. However, Wagner Lighting does not consider these disclosures to be a compromise of the confidential nature of the material. During conference calls on the twentieth day of May, 1991, Allegro MicroSystems, Inc. of Concord, N.H. and Exar Corp. of San Jose, California were given this information. These companies are designers and manufacturers of custom integrated circuits (IC) which would be used to control Wagner Lighting's flasher. Both of the companies were being interviewed as potential suppliers of the solid state IC that would help perform the functions listed in this document. Prior to this date, both of these companies had signed a non-disclosure agreement concerning any information that would be given to them by Wagner Lighting concerning purposed flasher development. The same information was shared again with Exar in meetings at Wagner Lighting on June 25-27, 1991.

This information was also disclosed to one of our customers. On three (3) separate dates, May 9 and 29, 1991 and June 13, 1991, This information was shared with the General Motors (GM) Flasher Task Force in Detroit. The GM Flasher Task Force is developing a new flasher specification for the corporation. Wagner Lighting felt this information was important for future flasher technology and needed GM's feedback as a customer. The other competitors, who are also involved with the GM Flasher Task Force, were asked to leave the room before this information was disclosed. Therefore, to the best of our knowledge, it was only disclosed to GM personnel.

Wagner Lighting does not feel that any of these disclosures is a compromise to the confidentiality of the following ideas because Wagner Lighting has applied for a patent for these ideas. (Patent application WLD-019749)

Per 512 4b3iv, Wagner Lighting knows of no other disclosure, public or private.

Per 512 4b3v, Wagner Lighting knows of no prior determination of these ideas.

Per 512 4b3vi, Wagner Lighting feels that the disclosure of these ideas would be harmful due to two (2) reasons. One, Wagner Lighting is planning on applying for foreign patents and the disclosure of these ideas would jeopardize these applications. Second, if the US patent is not granted, it would take away the competitive advantage of these ideas.

Per 512 4b3vii, Wagner Lighting sees no reason why this disclosure would impair NHTSA's ability to obtain similar information in the future.

Per 512 4b3viii, Wagner Lighting sees no reason why this disclosure would impair any other government interests.

Per 512 4b3ix, Wagner lighting request that these ideas be held as confidential until such time that US and European patents are awarded.

Per 512 5a, Wagner Lighting feels that the denial of confidentiality would result in competitive harm.

DESCRIPTION

The present conflict involves turn signal flashers, hazard warning flashers, and combination flashers, which perform the functions of both previously listed flashers. The conflict centers around FMVSS 108.

Previous to the 3 terminal, 3 lamp electronic/relay flasher, automobile systems utilized two 2-terminal thermal flashers. One flasher operated the automobile signal lamps for the turn signal mode, the other for hazard warning. Still today, the two 2-terminal flashers are used in 754 of the vehicles made in the United States.

The turn signal flasher would operate in a "steady on" condition if a lamp was lost (i.e. lamp outage) in the turn signal mode. This was to indicate to the driver that a lamp had failed. The hazard warning flasher would operate at the same speed regardless of the number of lamps, down to two lamps. The constant speed was required to maximize the visual perception of the flashing lamps, no matter how many lamps had failed. Both the turn signal and the hazard warning flashers are required to operate within the unshaded polygon shown in Figure 1.

FMVSS 108 was written to agree with the above discussion. The actual laws read:

FMVSS 108 (reference SAE J945 (3.0)) "...The previous operating tolerances shall apply for loads of two signal lamps, and the maximum design load..." where the tolerances are the unshaded polygon in figure 2.

FMVSS 108 (reference SAE J588e (4.5)) "failure of one or more turn signal lamps to operate should be indicated by a "steady on", "steady off", or by a significant change in the flashing rate of the illuminated indicator."

In the 1980's, electronic based flashers were introduced into the market. Presently, most are three terminal (battery, load, and ground) relay based flashers. (note: there is a two terminal, transistor based flasher (battery and load) under development at Wagner Lighting). These electronic flashers are required to operate within the same unshaded polygon in Figure I during the normal turn signal and in the hazard warning mode. Because the flash rate/duty cycle window is so wide, the technology of the flashers on the market today have wide variations in flash rate over temperature. Therefore, the flash rate had to be doubled for the lamp outage condition in turn signal mode to meet the "significant change" required in FMVSS.

As automobile designers began to cut costs, the electronic/relay flashers were used as combination flashers, both turn signal and hazard warning mode. However, using the flasher in this application for a 3 lamp turn signal/6 lamp hazard system introduced a conflict with the FMVSS laws. The units were design to double in flash rate when there were only 2 lamps in the system. This would indicate a lamp out for the turn signal mode.

However, if a automobile had 4 lamps out while in hazard mode, the flasher would also double in flash rate. There would be two lamps flashing in hazard mode outside the unshaded polygon and therefore not within the optimum perception region of other drivers. Such an occurrence would be rare case, but it is possible and therefore is a safety issue.

The present solution to the problem is the electronic/relay flasher designers plan to add a terminal to the flasher that would indicate whether the vehicle is in turn signal or hazard warning. A special IC would be designed to monitor this terminal, and adjust the flash rate accordingly.

This solution will require an additional terminal on the flasher, an additional plug, associated wiring, and a new switch design. All of these will add cost to the automotive wiring system.

Wagner Lighting has a solution to the problem.

The proposed lamp outage indication will remain within the acceptable performance range of FVMSS 108 represented in Figure 1.

Figure 1 GRAPH - FMVSS 108 POLYGON (Graph omitted)

I Michael D. Incorvaia, pursuant to the provisions of 49 CFRS12. state as follows:

(1) I am Manufacturing Engineering Manager, and I am authorized by Cooper Industries Wagner Lighting Division, hereinafter written as Wagner Lighting, to execute documents on behalf of Wagner Lighting.

(2) The information contained in the following letter to the Office of Chief Counsel is confidential and proprietary data and is being submitted with the claim that it is entitled to confidential treatment under 5 U.S.C #22(b)(4).

(3) I have personally inquired of the responsible Wagner Lighting personnel who have authority in the normal course of business to release the information for which a claim of confidentiality has been made to ascertain whether such information has ever been released outside Wagner Lighting.

(4) Based upon such inquiries, to the best of my knowledge, information, and belief, the information for which Wagner Lighting has claimed confidential treatment has never been released or become available outside Wagner Lighting except as hereinafter specified:

(5) I make no representations beyond those contained in this certificate and in particular, I make no representations as to whether this information may become available outside Wagner Lighting because of unauthorized or inadvertent disclosure except as stated in paragraph 4; and

(6) I certify under penalty of perjury that the foregoing is true and correct. Executed on this the tenth day of July, 1991.

Michael D. Incorvaia