Detroit Diesel DDEC VI Application And Installation page 250

FEATURES
Cruise Control or Road Speed Limit with Engine Brake
The Engine Brake option can also provide Engine Brake capability when the vehicle is in Cruise
Control or Road Speed Limit. For example, if the vehicle is going down hill in Cruise Control
while the engine brake is selected, the ECU will control the amount of Engine Brake with respect
to the Cruise Control set speed. The level of Engine Brake (low, medium, high) selected with the
dash switches will be the maximum amount of engine braking the ECU allows.
Each engine braking level has a hysteresis for actuating the engine brake or for deactivating
the engine brake.
Engine Brake Disable
The Engine Brake Disable option uses an input which is switched to ground whenever a vehicle
system, such as a traction control device, does not allow engine braking to occur. This option is
required for most automatic transmissions.
DDEC VI also supports the J1939 message to disable engine brakes (TSC1 command to source
address 15).
Engine Brake Active
The Engine Brake Active option uses a digital output that can be used to drive an Engine Brake
Active lamp. This output is switched to battery ground whenever the engine brake is active.
Engine Fan Braking
The Engine Fan Braking option turns on the cooling fan when the engine brake level is high and
DDEC fan control is enabled. This creates about 20 to 40 hp additional engine braking power
depending on the size of the cooling fan. For additional information, refer to section 5.11, "Fan
Controls."
Clutch Released Input
The Clutch Released input will prevent the engine brakes from being turned on when the clutch is
pressed. This input is required for use with manual transmissions. Refer to section 4.1, "Digital
Inputs," for additional information.
Min Vehicle Speed for Engine Brakes
This option will disable the engine brakes until a minimum vehicle speed is reached. A Vehicle
Speed Sensor (VSS) is required. Refer to section 3.6.6, "Vehicle Speed Sensor," for additional
information.
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All information subject to change without notice. (Rev. 01/07)
7SA827 0701 Copyright © 2007 DETROIT DIESEL CORPORATION