Description / Abstract:
Introduction
Note: Nothing in this standard supercedes
applicable laws and regulations.
Note: In the event of conflict between the
English and domestic language, the English language shall take
precedence.
Purpose. To demonstrate compliance to Federal
Motor Vehicle Safety Standard (FMVSS) 126 Electronic Stability
Control Systems section 5.4:
S5.4 Electronic Stability Control (ESC) Off and Other
System Controls. The manufacturer may include an "ESC Off"
control whose only purpose is to place the ESC system in a mode or
modes in which it will no longer satisfy the performance
requirement of S5.2.1 (1.0 s yaw velocity ratio), S5.2.2 (1.75 s
yaw velocity ratio) and S5.2.3 (1.07 s lateral displacement).
Manufacturers may also provide controls for other systems that have
an ancillary effect upon ESC operation. Controls of either kind
that place the ESC system in a mode in which it will no longer
satisfy the performance requirements of S5.2.1, S5.2.2 and S5.2.3
are permitted, provided that:
S5.4.1 The vehicle's ESC system must always
return to the manufacturer's original default ESC mode that
satisfies the requirements of S5.1 and S5.2 at the initiation of
each new ignition cycle, regardless of what ESC mode the driver had
previously selected, unless (a) the vehicle is in a low-range
four-wheel drive configuration selected by the driver on the
previous ignition cycle that is designed for low-speed, off-road
driving, or (b) the vehicle is in a four-wheel drive configuration
selected by the driver on the previous ignition cycle that is
designed for operation hat higher speeds on snow-, sand- or
dirt-packed roads and that has the effect of locking the drive
gears at the front and rear axles together, provided that the
vehicle meets the stability performance requirements of S5.2.1 and
S5.2.2 in this mode.
S5.4.2 In addition to the requirements of
S5.4.1, if the vehicles ESC system has more than one ESC mode that
satisfies the requirements of S5.1 and S5.2 within the drive
configuration selected of the previous ignition cycle, the system
must return to the manufacturer's original default ESC mode.
S5.4.3 As of September 1, 2011, a control whose
only purpose is to place the ESC system in a mode or modes in which
it will no longer satisfy the performance requirements of S5.2.1,
F5.2.2 and S5.2.3 must be identified by the symbol shown for "ESC
Off" in Table 1 of Standard No. 101 (49 Code of Federal Regulations
(CFR) 571.101) or the text, "ESC Off" as listed under "Word(s) or
Abbreviations" in Table 1 of Standard No. 101 (49 CFR 571.101).
S5.4.4 A control for another system that has
the ancillary effect of placing the ESC system in a mode in which
it no longer satisfies the performance requirements of S5.2.1,
S5.2.2 and S5.2.3 need not be identified by the "ESC Off"
identifiers in Table 1 of Standard No. 101 (49 CFR 157.101), but
the ESC status must be identified by the "ESC Off" Telltale in
accordance with S5.5, as of September 1, 2011, except if the
vehicle is in a four-wheel drive high gear configuration that has
the effect of locking the drive gears at the front and rear axles
together provided the vehicle meets the stability performance
criteria of S5.2.1 and S5.2.2.
Applicability. This procedure is applicable to
passenger vehicles and light trucks up to 4535.9 kg Gross Vehicle
Weight (GVW) sold in the United States.
Remarks. Not applicable.