Sec. 5.53.  Odometers

# A.  Application

**A.1.** - This code applies to odometers that are used or are to be
used to determine the charges for rent or hire of passenger vehicles and
trucks and buses.  (When official examinations are undertaken on
odometers that form the basis for the payment of fees or taxes to, or
the preparation of reports for, governmental agencies, and in similar
cases, the requirements of this code shall be applied insofar as they
are applicable and appropriate to the conditions of such special uses.)

(Amended 1977)

**A.2.** - This code does not apply to taximeters (for which see Sec.
5.54; Code for Taxi­meters). 

(Amended 1977)

**A.3.** - See also Sec. 1.10; General Code requirements.

## S.  Specifications

**S.1.  Design of Indicating Elements.**

> **S.1.1. General.** - The primary indicating element of an odometer
> may be:
>
> \(a\) the distance‑traveled portion of the \"sp­eedom­eter\" assembly of
> a motor vehicle;
>
> \(b\) a special cable‑driven distance‑indicating device; or
>
> \(c\) a hub odometer attached to the hub of a wheel on a motor
> vehicle.
>
> (Amended 1977)
>
> **S.1.2. Units.** - An odometer shall indicate in terms of miles or
> kilo­meters. 
>
> (Amended 1977)
>
> **S.1.3.  Minimum Indicated Value.** - The value of the interval of
> indi­cated distance shall be:
>
> \(a\) for odometers indicating in kilometers, 0.1 kilometer; or
>
> \(b\) for odometers indicating in miles, 0.1 mile.
>
> (Amended 1977)[­]{.mark}
>
> **S.1.4. Advancement of Indicating Elements.** - The most sensitive
> indicating elements of an odometer may advance continuously or
> intermit­tently; all other elements shall advance intermittently. 
> Except when the indications are being returned to zero, the
> indications of an installed odometer shall be susceptible to
> advancement only by the rotation of the vehicle wheel or wheels.
>
> (Amended 1977)
>
> **S.1.5. Readability.** - Distance figures and their background shall
> be of sharply contrasting colors.  Figures indicat­ing tenth units
> shall be differen­tiated from other figures with different colors, or
> with a decimal point, or by other equally effective means.  Except
> during the period of advance of any decade to the next higher
> indication, only one figure in each decade shall be exposed to view.
> Any protective covering intended to be transparent shall be in such
> condition that it can be made transparent by ordinary cleaning of its
> exposed surface. 
>
> (Amended 1977)
>
> **S.1.6. Digital Indications and Representation.** - Digital
> indicating odometers (discontinuous registration) shall \"round off\"
> indications to the nearest minimum division or truncate indications to
> the lower minimum division.
>
> (Added 1990)

## N.  Notes

**N.1.  Testing Procedures.**

> **N.1.1. Test Methods.** - To determine compliance with distance
> tolerances, a distance test of an odometer shall be conducted using
> one or more of the following test methods:
>
> \(a\) Road Test. - A road test consists of driving the vehicle over a
> precisely measured road course.
>
> \(b\) Fifth-Wheel Test. - A fifth-wheel test consists of driving the
> vehicle over any reasonable road course and determining the distance
> actually traveled through the use of a mechanism known as a \"fifth
> wheel\" that is attached to the vehicle and that independently
> measures and indicates the distance.
>
> \(c\) Simulated-Road Test. - A simulated road test consists of
> determining the distance traveled by use of a roller device, or by
> computation from rolling circumference and wheel‑turn data.
>
> (Amended 1977)
>
> **N.1.2. Test Runs.** - Not less than two test runs shall be
> conducted. Acceleration and deceleration shall be carefully controlled
> to avoid spinning or skidding the wheels. 
>
> (Amended 1977)­
>
> **N.1.2.1. For Devices Indicating in Miles.** - The test runs shall be
> 2 miles in length, shall start from, and finish at, a dead stop with a
> minimum of 80 % of the run between 30 miles per hour and 45 miles per
> hour.
>
> (Added 1977)
>
> **N.1.2.2.  For Devices Indicating in Kilometers.** - The test runs
> shall be 3 kilometers in length, shall start from, and finish at, a
> dead stop with a minimum of 80 % of the run between 50 kilometers per
> hour and 75 kilometers per hour. 
>
> (Added 1977)
>
> **N.1.3. Test Conditions.**
>
> **N.1.3.1.  Tire Stabilization.** - Road tests or fifth-wheel tests
> shall be preceded by a run of at least 8 kilometers or 5 miles, for
> the purpose of stabilizing tire pressures. Simulated road tests on a
> roller device shall be made at stable tire pressures.
>
> (Amended 1977)
>
> **N.1.3.2.  Tire Pressure.** - At the completion of the test run or
> runs, the tires of the vehicle under test shall be checked to
> determine that the tire pressure is that operating tire pressure
> posted in the vehicle.  If not, the tire pressure should be adjusted
> to the posted tire pressure and further tests may be conducted to
> determine the operating characteristics of the odometer. 
>
> (Amended 1977)
>
> **N.1.3.3.  Vehicle Loading.**
>
> \(a\) **Passenger Load.** - During the distance test of an odometer,
> the vehicle may carry two persons.
>
> \(b\) **Truck Cargo Load.** - Truck odometers shall be tested by one
> of the following methods:
>
> \(1\) the truck is loaded with one-half of the maximum cargo load; or
>
> \(2\) unloaded if unloaded test tolerances are applied.
>
> (Amended 1977 and 1987)

# T.  Tolerances

**T.1. To Underregistration and to Overregistration. -** The tol­erances
hereinafter prescribed shall be applied to errors of underregistration
and errors of over­registration.

**T.2.  Tolerance Values.** - Except for unloaded trucks, maintenance
and acceptance tolerances on odometers shall be 4 % of the interval
under test.

(Amended 1977and 1987)

> **T.2.1. Tolerances for Unloaded Trucks.** - Maintenance and
> acceptance tolerances on truck odometers shall be 5 % for
> underregistration and 3 % for overregistration of the interval under
> test.
>
> (Added 1987)

# UR.  User Requirements

**UR.1. Inflation of Vehicle Tires.** - The operational tire pressure of
passenger vehicle and truck tires shall be posted in the vehicle and
tires shall be maintained at the posted pressure.

(Amended 1977)