Mack CSM 2010, Operator'S Handbook Manual

Page: 111 / 232

OPERATION 103
Cruise Control with the MACK PowerLeash™ Engine
Brake
When the MACK PowerLeash™ Engine Brake is enabled at the same time your V-MAC®
cruise control is in use, the engine brake automatically activates when necessary to slow the
vehicle to the cruise set point speed. You can select one of two possible options:
•
The engine brake is activated 2 mph above the cruise set point.
•
The engine brake is activated as soon as cruise control commands fueling to zero (vehicle
has just reached cruise set point and fuel has been turned off).
The first option is the more popular choice for highway use and is the default mode. Consult
your V-MAC® IV Vehicle Management and Control with Co-Pilot® Display Operator’s
Guide for more information about this option. Your local MACK dealer can change the
current selection.
The engine brake’s ability to control maximum vehicle speed is limited to the selected
retarding power of the engine brake. If the engine brake dash-mounted control switch is set
to the LOW position, only half of the available braking power is used. If the dash-mounted
control switch is set to the HIGH position, the cruise control invokes full engine brake power.
Note: Deactivating the cruise control function does not disable the engine brake.
The MACK PowerLeash™ Engine Brake may be activated or deactivated by other vehicle
systems such as ABS and Headway control systems. Refer to the literature concerning
these systems for additional information.