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DDEC IV SYSTEM
When the Cruise Control switch
is in the ON position, cruise
control is engaged by momentarily
contacting the “Set/Coast” switch
to the ON position. Holding the
switch in the ON position allows the
vehicle to slow to a lower speed.
Toggling the switch will result in a
one mile-per-hour (1.6 kph) decrease
in vehicle speed. If cruise control
has been disabled, toggling the
“Resume/Accel” switch restores the
vehicle to the previously set cruise
speed.
Using either the brake or the clutch
will disable cruise control.
Engine Brakes
Engine brakes are enabled by an
ON/OFF switch mounted on the dash.
A separate intensity switch is used to
select
low, medium or high
braking
power. The engine brakes will only
operate when the electronic foot pedal
assembly (EFPA) is fully released.
Disengaging the clutch will prevent
the engine brakes from operating.
Engine brakes will supply braking
power even when in cruise control.
The electronic control module (ECM)
will control the amount of engine
braking with respect to the cruise
control set speed. The maximum
amount of braking (
low, medium, high
)
is selected with the dash switches.
To avoid injury from loss of
vehicle control, do not activate
the Engine Brake system under
the following conditions:
On wet or slippery pavement,
unless the vehicle is equipped
with ABS (anti-lock braking
system) and you have had
prior experience driving
under these conditions.
When driving without a trailer
(bobtailing) or pulling and
empty trailer.
If the tractor drive wheels
begin to lock or there is
fishtail motion after the
Engine Brake is activated.
Deactivate the brake system
immediately, if this occurs.
Failure to observe these
precautions may result in
loss of vehicle control and/or
personal injury.
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All information subject to change without notice.
(Rev. 01/ 04)
6SE550 0401
Copyright © 2004 DETROIT DIESEL CORPORATION