[Code of Federal Regulations]
[Title 49, Volume 4]
[Revised as of October 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR393.22]

[Page 1058-1059]
 
                        TITLE 49--TRANSPORTATION
 
        CHAPTER III--FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION,
                      DEPARTMENT OF TRANSPORTATION
 
PART 393--PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION--Table of Contents
 
    Subpart B--Lighting Devices, Reflectors, and Electrical Equipment
 
Sec. 393.22  Combination of lighting devices and reflectors.

    (a) Permitted combinations. Except as provided in paragraph (b) of 
this section, two or more lighting devices and reflectors (whether or 
not required by the rules in this part) may be combined optically if--
    (1) Each required lighting device and reflector conforms to the 
applicable rules in this part; and
    (2) Neither the mounting nor the use of a nonrequired lighting 
device or reflector impairs the effectiveness of a required lighting 
device or reflector or causes that device or reflector to be 
inconsistent with the applicable rules in this part.
    (b) Prohibited combinations. (1) A turn signal lamp must not be 
combined optically with either a head lamp or other lighting device or 
combination of lighting devices that produces a greater intensity of 
light than the turn signal lamp.
    (2) A turn signal lamp must not be combined optically with a stop 
lamp unless the stop lamp function is always deactivated when the turn 
signal function is activated.

[[Page 1059]]

    (3) A clearance lamp must not be combined optically with a tail lamp 
or identification lamp.

[39 FR 26908, July 24, 1974]