[Code of Federal Regulations]
[Title 40, Volume 29]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR600.111-80]

[Page 889-891]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 600_FUEL ECONOMY OF MOTOR VEHICLES--Table of Contents
 
    Subpart B_Fuel Economy Regulations for 1978 and Later Model Year 
                       Automobiles_Test Procedures
 
Sec. 600.111-80  Test procedures.

    (a) The test procedures to be followed for generation of the city 
fuel economy data are those prescribed in Sec. Sec. 86.127-94 through 
86.138-78 of this chapter, as applicable. (The evaporative and refueling 
loss portions of the test procedure may be omitted unless specifically 
required by the Administrator.)
    (b) The test procedures to be followed for generation of the highway 
fuel economy data are those specified in Sec. 600.111-78 (b) through 
(h) inclusive.
    (1) The Highway Fuel Economy Dynamometer Procedure consists of a 
preconditioning highway driving sequence and a measured highway driving 
sequence.
    (2) The highway fuel economy test is designated to simulate non-
metropolitan driving with an average speed of 48.6 mph and a maximum 
speed of 60 mph. The cycle is 10.2 miles long with 0.2 stops per mile 
and consists of warmed-up vehicle operation on a chassis dynamometer 
through a specified driving cycle. A proportional part of the diluted 
exhaust emissions is collected continuously for subsequent analysis 
using a constant volume (variable dilution) sampler. Diesel dilute 
exhaust is continuously analyzed for hydrocarbons using a heated sample 
line and analyzer.
    (3) Except in cases of component malfunction or failure, all 
emission control systems installed on or incorporated in a new motor 
vehicle must be functioning during all procedures in this subpart. The 
Administrator may authorize maintenance to correct component malfunction 
or failure.
    (c) Transmission. The provisions of Sec. 86.128 of this chapter 
apply for vehicle transmission operation during highway fuel economy 
testing under this subpart.
    (d) Road load power and test weight determination. Section 86.129 of 
this chapter applies for determination of road load power and test 
weight for highway fuel economy testing. The test weight for the testing 
of a certification vehicle will be that test weight specified by the 
Administrator under the provisions of part 86. The test weight for a 
fuel economy data vehicle will be that test weight specified by the 
Administrator from the test weights covered by that vehicle 
configuration. The Administrator will base his selection of a test 
weight on the relative projected sales volumes of the various test 
weights within the vehicle configuration.

[[Page 890]]

    (e) Vehicle preconditioning. The Highway Fuel Economy Dynamometer 
Procedure is designed to be performed immediately following the Federal 
Emission Test Procedure, Sec. Sec. 86.127 through 86.138 of this 
chapter. When conditions allow, the tests should be scheduled in this 
sequence. In the event the tests cannot be scheduled within three hours 
of the Federal Emission Test Procedure (including one hour hot soak 
evaporation loss test, if applicable) the vehicle should be 
preconditioned as in paragraph (e)(1) or (2) of this section, as 
applicable.
    (1) If the vehicle has experienced more than three hours of soak (68 
[deg]F-86 [deg]F) since the completion of the Federal Emission Test 
Procedure, or has experienced periods of storage outdoors, or in 
environments where soak temperature is not controlled to 68 [deg]F-86 
[deg]F, the vehicle must be preconditioned by operation on a dynamometer 
through one cycle of the EPA Urban Dynamometer Driving Schedule, Sec. 
86.115 of this chapter.
    (2) In unusual circumstances where additional preconditioning is 
desired by the manufacturer, the provisions of paragraph (a)(3) of Sec. 
86.132 of this chapter apply.
    (f) Highway fuel economy dynamometer procedure. (1) The dynamometer 
procedure consists of two cycles of the Highway Fuel Economy Driving 
Schedule (Sec. 600.109 (b)) separated by 15 seconds of idle. The first 
cycle of the Highway Fuel Economy Driving Schedule is driven to 
precondition the test vehicle and the second is driven for the fuel 
economy measurement.
    (2) The provisions of paragraphs (b), (c), (e), (f), (g), and (h) of 
Sec. 86.135 Dynamometer procedure of this chapter, apply for highway 
fuel economy testing.
    (3) Only one exhaust sample and one background sample are collected 
and analyzed for hydrocarbons (except diesel hydrocarbons which are 
analyzed continuously), carbon monoxide, and carbon dioxide.
    (4) The fuel economy measurement cycle of the test includes two 
seconds of idle indexed at the beginning of the second cycle and two 
seconds of idle indexed at the end of the second cycle.
    (g) Engine starting and restarting. (1) If the engine is not running 
at the initiation of the highway fuel economy test (preconditioning 
cycle), the start-up procedure must be according to the manufacturer's 
recommended procedures.
    (2) False starts and stalls during the preconditioning cycle must be 
treated as in paragraphs (d) and (e) of Sec. 86.136 of this chapter. If 
the vehicle stalls during the measurement cycle of the highway fuel 
economy test, the test is voided, corrective action may be taken 
according to Sec. 86.079-25 of this chapter, and the vehicle may be 
rescheduled for test. The person taking the corrective action shall 
report the action so that the test records for the vehicle contain a 
record of the action.
    (h) Dynamometer test run. The following steps must be taken for each 
test:
    (1) Place the drive wheels of the vehicle on the dynamometer. The 
vehicle may be driven onto the dynamometer.
    (2) Open the vehicle engine compartment cover and position the 
cooling fan(s) required. Manufacturers may request the use of additional 
cooling fans for additional engine compartment or under-vehicle cooling 
and for controlling high tire or brake temperatures during dynamometer 
operation.
    (3) Preparation of the CVS must be performed before the measurement 
highway driving cycle.
    (4) Equipment preparation. The provisions of paragraphs (b) (3) 
through (5) inclusive of Sec. 86.137 of this chapter apply for highway 
fuel economy test except that only one exhaust sample collection bag and 
one dilution air sample collection bag need be connected to the sample 
collection systems.
    (5) Operate the vehicle over one Highway Fuel Economy Driving 
Schedule cycle according to the dynamometer driving schedule specified 
in paragraph (b) of Sec. 600.109.
    (6) When the vehicle reaches zero speed at the end of the 
preconditioning cycle, the driver has 17 seconds to prepare for the 
emission measurement cycle of the test. Reset and enable the roll 
revolution counter.
    (7) Operate the vehicle over one Highway Fuel Economy Driving 
Schedule cycle according to the dynamometer driving schedule specified 
in paragraph

[[Page 891]]

(b) of Sec. 600.109 while sampling the exhaust gas.
    (8) Sampling must begin two seconds before beginning the first 
acceleration of the fuel economy measurement cycle and must end two 
seconds after the end of the deceleration to zero. At the end of the 
deceleration to zero speed, the roll or shaft revolutions must be 
recorded.

[42 FR 45657, Sept. 12, 1977, as amended at 43 FR 52929, Nov. 14, 1978; 
59 FR 16309, Apr. 6, 1994]