[Code of Federal Regulations]
[Title 49, Volume 5]
[Revised as of October 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR571.104]

[Page 199-201]
 
                        TITLE 49--TRANSPORTATION
 
                            OF TRANSPORTATION
 
PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS--Table of Contents
 
            Subpart B--Federal Motor Vehicle Safety Standards
 
Sec. 571.104  Standard No. 104; Windshield wiping and washing systems.

    S1. Scope. This standard specifies requirements for windshield 
wiping and washing systems.
    S2. Application. This standard applies to passenger cars, 
multipurpose passenger vehicles, trucks, and buses.
    S3. Definitions. The term seating reference point is substituted for 
the terms manikin H point, manikin H point with seat in rearmost 
position and H point wherever any of these terms appear in

[[Page 200]]

any SAE Standard or SAE Recommended Practice referred to in this 
standard.
    Daylight opening means the maximum unobstructed opening through the 
glazing surface, as defined in paragraph 2.3.12 of section E, Ground 
Vehicle Practice, SAE Aerospace-Automotive Drawing Standards, September 
1963.
    Glazing surface reference line means the line resulting from the 
intersection of the glazing surface and a horizontal plane 635 
millimeters above the seating reference point, as shown in Figure 1 of 
SAE Recommended Practice J903a, ``Passenger Car Windshield Wiper 
Systems,'' May 1966.
    Overall width means the maximum overall body width dimension 
``W116'', as defined in section E, Ground Vehicle Practice, SAE 
Aerospace-Automotive Drawing Standards, September 1963.
    Plan view reference line means--
    (a) For vehicles with bench-type seats, a line parallel to the 
vehicle longitudinal centerline outboard of the steering wheel 
centerline 0.15 times the difference between one-half of the shoulder 
room dimension and the steering wheel centerline-to-car-centerline 
dimension as shown in Figure 2 of SAE Recommended Practice J903a, May 
1966; or
    (b) For vehicles with individual-type seats, either--
    (i) A line parallel to the vehicle longitudinal centerline which 
passes through the center of the driver's designated seating position; 
or
    (ii) A line parallel to the vehicle longitudinal centerline located 
so that the geometric center of the 95 percent eye range contour is 
positioned on the longitudinal centerline of the driver's designated 
seating position.
    Shoulder room dimension means the front shoulder room dimension 
``W3'' as defined in section E, Ground Vehicle Practice, SAE Aerospace-
Automotive Drawing Standards, September 1963.
    95 percent eye range contour means the 95th percentile tangential 
cutoff specified in SAE Recommended Practice J941, ``Passenger Car 
Driver's Eye Range,'' November 1965.
    S4. Requirements.
    S4.1  Windshield wiping system. Each vehicle shall have a power-
driven windshield wiping system that meets the requirements of S4.1.1.
    S4.1.1  Frequency.
    S4.1.1.1  Each windshield wiping system shall have at least two 
frequencies or speeds.
    S4.1.1.2  One frequency or speed shall be at least 45 cycles per 
minute regardless of engine load and engine speed.
    S4.1.1.3  Regardless of engine speed and engine load, the highest 
and one lower frequency or speed shall differ by at least 15 cycles per 
minute. Such lower frequency or speed shall be at least 20 cycles per 
minute regardless of engine speed and engine load.
    S4.1.1.4  Compliance with subparagraphs S4.1.1.2 and S4.1.1.3 may be 
demonstrated by testing under the conditions specified in sections 4.1.1 
and 4.1.2 of SAE Recommended Practice J903a, May 1966.
    S4.1.2  Wiped area. When tested wet in accordance with SAE 
Recommended Practice J903a, May 1966, each passenger car windshield 
wiping system shall wipe the percentage of Areas A, B, and C of the 
windshield (established in accordance with S4.1.2.1) that (1) is 
specified in column 2 of the applicable table following subparagraph 
S4.1.2.1 and (2) is within the area bounded by a perimeter line on the 
glazing surface 25 millimeters from the edge of the daylight opening.
    S4.1.2.1  Areas A, B, and C shall be established as shown in Figures 
1 and 2 of SAE Recommended Practice J903a, May 1966, using the angles 
specified in Columns 3 through 6 of Table I, II, III, or IV, as 
applicable.

                     Table I--Passenger Cars of Less Than 1520 Millimeters in Overall Width
----------------------------------------------------------------------------------------------------------------
                                                                      Column           Angles in degrees
                                                                       2--   -----------------------------------
                                                                     Minimum
                           Column 1--Area                            percent   Column   Column   Column   Column
                                                                      to be   3--Left    4--     5--Up   6--Down
                                                                      wiped             Right
----------------------------------------------------------------------------------------------------------------
A..................................................................       80       16       49        7        5
B..................................................................       94       13       46        4        3
C..................................................................       99        7       15        3        1
----------------------------------------------------------------------------------------------------------------


[[Page 201]]


            Table II--Passenger Cars of 1520 or More But Less Than 1630 Millimeters in Overall Width
----------------------------------------------------------------------------------------------------------------
                                                                      Column           Angles in degrees
                                                                       2--   -----------------------------------
                                                                     Minimum
                           Column 1--Area                            percent   Column   Column   Column   Column
                                                                      to be   3--Left    4--     5--Up   6--Down
                                                                      wiped             Right
----------------------------------------------------------------------------------------------------------------
A..................................................................       80       17       51        8        5
B..................................................................       94       13       49        4        3
C..................................................................       99        7       15        3        1
----------------------------------------------------------------------------------------------------------------


            Table III--Passenger Cars of 1630 or More But Less Than 1730 Millimeters in Overall Width
----------------------------------------------------------------------------------------------------------------
                                                                      Column           Angles in degrees
                                                                       2--   -----------------------------------
                                                                     Minimum
                           Column 1--Area                            percent   Column   Column   Column   Column
                                                                      to be   3--Left    4--     5--Up   6--Down
                                                                      wiped             Right
----------------------------------------------------------------------------------------------------------------
A..................................................................       80       17       53        9        5
B..................................................................       94       14       51        5        3
C..................................................................       99        8       15        4        1
----------------------------------------------------------------------------------------------------------------


                      Table IV--Passenger Cars of 1730 or More Millimeters in Overall Width
----------------------------------------------------------------------------------------------------------------
                                                                      Column           Angles in degrees
                                                                       2--   -----------------------------------
                                                                     Minimum
                           Column 1--Area                            percent   Column   Column   Column   Column
                                                                      to be   3--Left    4--     5--Up   6--Down
                                                                      wiped             Right
----------------------------------------------------------------------------------------------------------------
A..................................................................       80       18       56       10        5
B..................................................................       94       14       53        5        3
C..................................................................       99       10       15        5        1
----------------------------------------------------------------------------------------------------------------

    S4.2  Windshield washing system.
    S4.2.1  Each passenger car shall have a windshield washing system 
that meets the requirements of SAE Recommended Practice J942, 
``Passenger Car Windshield Washer Systems,'' November 1965, except that 
the reference to ``the effective wipe pattern defined in SAE J903, 
paragraph 3.1.2'' in paragraph 3.1 of SAE Recommended Practice J942 
shall be deleted and ``the areas established in accordance with 
subparagraph S4.1.2.1 of Motor Vehicle Safety Standard No. 104'' shall 
be inserted in lieu thereof.
    S4.2.2  Each multipurpose passenger vehicle truck, and bus shall 
have a windshield washing system that meets the requirements of SAE 
Recommended Practice J942, November 1965, except that the reference to 
``the effective wipe pattern defined in SAE J903, paragraph 3.1.2'' in 
paragraph 3.1 of SAE Recommended Practice J942 shall be deleted and 
``the pattern designed by the manufacturer for the windshield wiping 
system on the exterior surface of the windshield glazing'' shall be 
inserted in lieu thereof.

[36 FR 22902, Dec. 2, 1971, as amended at 58 FR 13023, Mar. 9, 1993; 60 
FR 13643, Mar. 14, 1995; 63 FR 51000, Sept. 24, 1998]