Interpretation ID: 18981.wkm
Mr. Clive Glanville - PM
Italamec
Direzione Tecnica
Via R. Geymet, 25
10060 Campiglione Fenile (Torino)
Italy
Dear Mr. Glanville:
Please pardon the delay in responding to your letter telefaxed to Walter Myers of my staff in which you asked us to analyze the configuration of your back door latch system and provide you a "conformance certificate." You enclosed drawings of your latch system. Following a telephone conversation with Mr. Myers on February 12, 1999, you sent him another telefax in which you stated that you need "confirmation that when two tailgate latches are fitted to a tailgate, as to whether they both must have two safety positions and must meet the strength requirements." You further stated in this telefax that both latches are identical, therefore they do not constitute a "primary and secondary latch system." You attached a drawing to the February 12 letter depicting the back door of a multipurpose passenger vehicle. The drawing shows the latches located on either side of and near the bottom of the door. We have reviewed your latch system as you requested, but are not able to provide you a "conformance certificate," as discussed below.
This agency, the National Highway Traffic Safety Administration (NHTSA), has the statutory authority to issue Federal motor vehicle safety standards (FMVSS) applicable to new motor vehicles and new items of motor vehicle equipment. The basic statute, commonly referred to as the Safety Act, establishes a self-certification system in which the manufacturers of motor vehicles and motor vehicle equipment themselves certify that their product complies with all applicable FMVSSs in effect on the date of manufacture. NHTSA checks compliance with the FMVSSs by purchasing motor vehicles and equipment and testing them. The agency also investigates defects relating to motor vehicle safety. Because of that self-certification system, NHTSA cannot issue certificates of conformance.
Paragraph S4.4.1, Federal Motor Vehicle Safety Standard (Standard) No. 206, Door locks and door retention components (copy enclosed), requires that "[E]ach back door system shall be equipped with at least one primary latch and striker assembly" (emphasis added). Also with respect to a back door or a back door system, a "primary door latch," as defined in S3, means "the latch or latches equipped with both the fully latched position and the secondary latched position"(emphasis added). The "fully latched position" is described in Society of Automotive Engineers (SAE) Recommended Practice J839, Passenger Car Side Door Latch Systems, June 1991, as "[T]he attitude that exists between the latch and striker when the door is securely positioned in the fully closed position." The "secondary latched position" is described in SAE J839 as "[T]he attitude that exists between the latch and striker when the latch holds the door in a position less than fully closed." The secondary latched position serves as a backup to the fully latched position in the event the latter is not properly engaged, and adds an additional level of protection in the event the latch fails while in the fully latched position.
Back doors may, but are not required, to have one or more auxiliary latches, which is a latch other than the primary latch or latches in a multi-latch door system. (1)
Auxiliary latches are typically used in double cargo door systems where the primary latch or latches directly connect the left and right segments of the door system to each other while the auxiliary latch or latches secure one segment of the door system to the roof and/or the floor of the vehicle.
Since a back door latch system is only required to have one primary latch, your dual latch system may consist of a primary latch and one or more auxiliary latches. However, if you have two primary latches, that is, ones with both the fully and secondary latched positions, then both must meet the strength requirements in both the fully latched and secondary latched positions as specified in S4.4.1.1 through S4.4.1.4.
I am enclosing for your additional information copies of fact sheets prepared by this agency entitled Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment, and Where to Obtain NHTSA's Safety Standards and Regulations.
I hope this information is helpful to you. Should you have any further questions or need additional information, feel free to contact Mr. Myers at this address or at (202) 366-2992, or by telefax at (202) 366-3820.
Sincerely,
Frank Seales, Jr.
Chief counsel
Enclosure
ref:206
d.7/15/99
1. Standard No. 206 does not refer to multiple latch systems as "primary" and "secondary" but, as discussed above, to "primary" and "auxiliary." We assume, therefore, that you mean that your latch systems do not fall into the categories of "primary" and "auxiliary."