PEC017
5/3/2018
Page
38
of
105
Manual Mode is the default setting for the PACCAR Engine Brake when
the PACCAR Engine Brake ON/OFF switch is ON and cruise control is
ON and inactive. It behaves the same way as the Manual Mode
described in Standard Features portion of this section.
Coast Mode allows the engine to provide braking when the PACCAR
Engine Brake ON/OFF switch is ON, the Cruise Control is ON and
inactive, and the service brake is applied. The PACCAR Engine Brake
will de-activate in Coast Mode when the service brake pedal is released
or cruise control is activated.
Latch Mode allows the engine to provide braking when the PACCAR
Engine Brake ON/OFF switch is ON, cruise control is ON and inactive,
and the service brake pedal is applied. Latch Mode will continue to
provide braking after the service brake pedal is released and will de-
activate when the accelerator pedal is applied or cruise control is
activated.
The engine can be programmed to delay the activation of the engine brake, if
needed, using
Time Delay for Retarder Activation (
. For example, the driver
may wish to deactivate Cruse Control by quickly pressing the brake pedal without
activating the engine brake when using Coast or Latch mode. Specifying a delay
would allow this to occur, but still provide engine braking when the driver presses the
brake pedal for a prolonged period during a braking event. The engine brake may
also be programmed to be disabled when the transmission is out of gear with
Engine
Brake Disabled When Out of Gear (
to assist the driver while shifting.
The engine brake will become disabled when the vehicle speed falls below
Minimum
Vehicle Speed for Engine Brake Activation (
Downhill Speed Control allows the engine to provide braking when the PACCAR
Engine Brake ON/OFF switch is ON, Cruise Control is active and the vehicle speed
exceeds the Cruise Control target speed plus the
Auto-Retarder Vehicle Speed
Offset (
. A large offset will reduce engine brake usage, while a lower offset will
increase engine brake usage. A lower offset is recommended for vehicles operating
in steep terrain. Downhill Speed Control will deactivate when the vehicle speed has
been reduced to the Cruise Control target speed or when Cruise Control is
deactivated. Downhill Speed Control will function independently of all other PACCAR
Engine Brake parameters.
The Downhill Speed Limiter (DSL) allows the engine to provide braking when the
PACCAR Engine Brake ON/OFF switch is ON and the vehicle speed exceeds the
Maximum Accelerator Pedal Vehicle Speed (
plus the
Downhill Speed Limiter
Vehicle Speed Offset
, The Downhill Speed Limiter will function independently
of all other PACCAR Engine Brake parameters.
In Manual Mode, the Downhill Speed Limiter will activate if the vehicle speed
exceeds the
Maximum Accelerator Pedal Vehicle Speed (
plus the
Downhill
Speed Limiter Vehicle Speed Offset (
. If the Downhill Speed Limiter is already
active, the PACCAR Engine Brake power will be increased, but if the Downhill Speed
Limiter is already at maximum capacity, the Downhill Speed Limiter will have no
effect on the PACCAR Engine Brake. The Downhill Speed Limiter will automatically
deactivate when the vehicle speed has been reduced to the
Maximum Accelerator
Pedal Vehicle Speed (
.
