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Interpretation ID: 1768y

Mr. Karl H. Mayer
Rules and Regulations
Dr.Ing.h.c.F.Porsche AG
Porschestrasse 42
Stuttgart--Zuffenhausen
West Germany

Dear Mr. Mayer:

This responds to your request for an interpretation of Federal Motor Vehicle Safety Standards No. l0l, Controls and Displays, and No. l02, Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect. You asked about the standards in connection with a new transmission and related gear shift mechanism that you are considering producing. I note that your accompanying request for confidentiality was withdrawn by an August l5, l988 letter signed by your attorney, effective September 30, l988.

You stated that the new transmission is characterized by two functions, a manual gear shift and an automatic gear shift, combined in a single unit. A motor vehicle incorporating the transmission does not have a clutch pedal. Operation of the transmission is entirely dependent on the position selected for the gear shift lever. The shift lever is located in the middle console, where it can be moved along either of two slots which are located essentially parallel to the longitudinal axis of the vehicle. The left slot (automatic function) is essentially the same as a conventional automatic transmission gear shift lever, with the following positions (in order): P R N D 3 2 l. At the D position (only) of the left slot, the gear shift lever can be transferred to the M (manual) position of the right slot (manual function). The right slot consists of the following positions (in order): + M -. When the gear shift lever is in the right slot, the driver can select a higher gear (+) or lower gear (-) by tapping the shift lever. The shift lever always returns to the "M" position after being tapped. You plan to provide two shift displays, one on the middle console and the other on the instrument panel.

You stated that you believe that a dual function transmission of the type described in your letter is permitted if it meets the various requirements of Standards No. l0l and l02 and asked whether we agree with your interpretation. You also asked three questions related to certain aspects of the transmission and related gear shift lever and shift displays. Your questions are responded to below.

By way of background information, and as noted in your letter, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of the manufacturer to ensure that its vehicles meet applicable requirements. The following represents our opinion based on the facts provided in your letter.

I agree with your basic contention that a dual function transmission of the type described in your letter is permitted if it, and the accompanying gear shift lever and shift displays, meet the various requirements of Standards No. l0l and l02. The performance requirements specified in the two standards do not prohibit dual function transmissions.

I have one primary comment concerning how you should evaluate Standards No. l0l and No. l02 with respect to the compliance of a vehicle equipped with the transmission. In some instances, these standards specify different requirements depending on whether a vehicle is equipped with a manual transmission or an automatic transmission. Thus, a critical issue is which of these requirements would need to be met by a vehicle equipped with your planned transmission. While you characterize the transmission as having two functions, a manual gear shift and an automatic gear shift, combined in a single unit, it is our opinion that the transmission is an automatic transmission for purposes of Federal motor vehicle safety standards. It is possible, of course, to manually control most conventional automatic transmissions, at least to some extent, by means of the gear shift lever, e.g., by shifting the lever from D to L. Your transmission would differ from a conventional automatic transmission primarily in having an additional means of manual control. However, the transmission would still be an automatic transmission. Vehicles equipped with the transmission would thus need to meet the requirements specified by Standards No. l0l and No. l02 for vehicles equipped with an automatic transmission, and not the requirements specified for vehicles equipped with a manual transmission.

I will now address your three specific questions. You stated that it appears to you that when the shift lever is in the manual slot, it is permissible to have the lever, after tapping to shift up or down, return to the original middle position, and asked for our interpretation on this point. We agree that this basic design is permitted under Standards No. l0l and No. l02.

Your second and third questions, which I will address together, concern the shift displays. You stated that you believe it is permissible for both of the dual shift pattern displays, i.e., the one on the middle console and the one on the instrument panel, to be constantly visible so that the driver can simultaneously see the currently used shift mode and also the alternative, and asked for our evaluation of this point. You also asked about the permissibility of two alternative instrument panel displays.

I will begin my discussion of these questions by identifying the relevant requirements of Standards No. l0l and No. l02. Section S3.2 of Standard No. l02 states that the "(i)dentification of shift lever positions of automatic transmissions . . . shall be permanently displayed in view of the driver." NHTSA has previously interpreted "position" to mean the shift lever positions in relation to each other and the position that the driver has selected at the time of selection. Therefore, the display of a gear lever sequence and a gear position indicator is required for automobiles equipped with automatic transmissions. NHTSA has previously interpreted the requirement for permanent display as requiring a display that can be seen regardless of the operating mode of the engine. Thus, it is not permissible for the required display to be visible (e.g., in the case of an electronic display, be activated) only when the key is in the ignition switch. (I note that on August 25, l988, NHTSA published a notice of proposed rulemaking to amend the requirement for permanent display. A copy is enclosed.)

Standard No. l0l specifies requirements for the location, identification and illumination of automatic gear position displays. Section S5.l requires that gear position displays must be visible to the driver under the conditions of S6. Section S6 provides that the driver is restrained by the crash protection equipment installed in accordance with Standard No. 208, Occupant Crash Protection, adjusted in accordance with the manufacturer's instructions. Section S5.3.l and Table 2 of the standard together require that automatic gear position displays be illuminated whenever the ignition switch and/or the headlamps are activated. The entry in Table 2 concerning the automatic gear position display references Standard No. l02.

Your design includes the following ten shift lever positions: P R N D 3 2 l + M -. Under section S3.2 of Standard No. l02, all of these positions must be permanently displayed, i.e., there must be a display of the l0 positions in relation to each other and there must be an indication of the position that the driver has selected. As indicated above, Standard No. l0l specifies requirements for the location, identification and illumination of automatic gear position displays.

The fact that your design would include more than one gear position display raises several issues, including (l) whether more than one display is permitted, (2) whether each display (where multiple displays are provided) must meet all of the requirements specified by Standards No. l0l and No. l02, and (3) whether multiple displays can be used to meet the requirements of the standards for gear position displays where no single display meets the requirements. It is our opinion that more than one display is permitted. It is also our opinion that if one display meets all of the requirements of Standards No. l0l and No. l02, the additional display(s) provided voluntarily by the manufacturer need not meet any particular requirements (except for section S5.3.5 of Standard No. l0l, which specifies requirements for sources of illumination not otherwise regulated by that standard). We have not previously found it necessary to address the issue of whether multiple displays can be used to meet the requirements of the standards for gear position displays where no single display meets the requirements. However, one commenter on the August 25, l988 notice cited above asked whether two displays could be used together to demonstrate compliance with section S3.2 of Standard No. l02. We plan to address that specific issue in the context of that rulemaking.

While it is not entirely clear from your letter, the display on the middle console may provide permanent display (including times when the ignition is not on) of the shift lever positions, i.e., a display of the l0 positions in relation to each other and an indication of the position selected by the driver. It appears, however, that illumination is not provided for this display. Given the reference in Standard No. l0l to Standard No. l02, it is our opinion that where multiple gear position displays are provided and one complies with Standard No. l02 and the others do not, the requirements of Standard No. l0l must be met for the display which complies with Standard No. l02.

If the display on the console fully met the requirements of Standards No. l0l and No. l02, it would be unnecessary for the additional display on the instrument panel to also meet the standards (with the exception of section S5.3.5 of Standard No. l0l, as noted above). I note that neither of the alternative instrument panel displays shown in your letter show all of the shift lever positions. While the displays do show P R N D 3 2 l, they show either 4 3 2 l or 4 3 M 2 l instead of + M -. If the instrument panel display, rather than the console display, was to be used to meet the requirements of section S3.2 of Standard No. l0l, it would be necessary for the display to show the l0 actual shift lever positions, including + M -. I also assume that the instrument panel display is not activated when the ignition is not on and thus does not provide a permanent display.

I would like to note that the discussion in the preceding paragraph should not be read as a suggestion that you change the instrument panel display to show + M - instead of 4 3 2 l or 4 3 M 2 l. One consequence of your design is that, in the manual mode, the driver would not know what gear the car was in from either observing the location of the gear shift lever or by knowing the shift lever position (+ M or -). Your design takes care of this, however, by providing an indication of actual gear position on the instrument panel display. Assuming that you can meet the requirements of Standards No. l0l and No. l02 by means of the console display, we believe that it would be a desirable feature of your design to indicate actual gear position on the voluntarily provided instrument panel display.

I hope this information is helpful. If you have any further questions concerning this matter, please contact me.

Sincerely,

Erika Z. Jones Chief Counsel

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