Mack CHM 2010, Руководство оператора

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124 OPERATION
Precautions When Installing Electrical Equipment
Connecting electrically powered or electrically controlled equipment to the vehicle may
cause interference with other vehicle components (e.g., the ABS system). The amount of
interference will depend on the operating frequency of any new signals and the degree to
which transient signals are coupled into the vehicle system.
Note: Whenever new electrical equipment is installed, it is the obligation of the installer
to ensure that the new equipment does not interfere with the proper operation of all other
electrical systems on the vehicle.
If new electrical equipment is installed, a vehicle checkout procedure should be performed.
1 Perform the checkout procedure under the following conditions:
•
Engine running
•
Brake system air pressure in operating range
•
Vehicle stationary
•
Brake pedal fully depressed
2 Operate the new equipment under all starting, running and shutdown conditions.
3 Listen for signs of air exhausting from ABS modulator valves (which is an indication of
an interference condition).
4 Correct all interference conditions before operating the vehicle.
Note: The center pin of the standard seven-pin trailer electrical connector has been
standardized as the dedicated connection for uninterrupted power for trailer ABS. This
pin is always hot when the tractor ignition is turned on.
DANGER
Some trailers manufactured prior to the
trailer ABS regulations may use the center
pin to power certain trailer auxiliary
equipment. The possibility exists that this
auxiliary equipment may be unexpectedly
activated by the truck or tractor electrical
system, resulting in personal injury or
damage to equipment. Caution must be
used when connecting the trailer electrical
connector to ensure that power to the
center pin will not unintentionally activate
any trailer auxiliary equipment.