[Code of Federal Regulations]
[Title 49, Volume 5]
[Revised as of October 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR393.49]

[Page 405-406]
 
                        TITLE 49--TRANSPORTATION
 
                      DEPARTMENT OF TRANSPORTATION
 
PART 393_PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION--Table of 
Contents
 
                            Subpart C_Brakes
 
Sec.  393.49  Control valves for brakes.

    (a) General rule. Except as provided in paragraphs (b) and (c) of 
this section, every motor vehicle manufactured after June 30, 1953, 
which is equipped with power brakes, must have the braking system so 
arranged that one application valve must when activated cause all of the 
service brakes on the motor vehicle or combination motor vehicle to 
operate. This requirement must not be construed to prohibit motor 
vehicles from being equipped with an additional valve to be used to 
operate the brakes on a trailer or trailers or as required for busses in 
Sec.  393.44.
    (b) Driveaway-Towaway Exception. This section is not applicable to 
driveaway-towaway operations unless the brakes on such operations are 
designed to be operated by a single valve.

[[Page 406]]

    (c) Surge brake exception. This requirement is not applicable to 
trailers equipped with surge brakes that satisfy the conditions 
specified in Sec.  393.48(d).

[72 FR 9871, Mar. 6, 2007]