Engine Brake Controls - Mbe900 And Mbe4000; Operation - Detroit Diesel DDEC VI Application And Installation

5.6 ENGINE BRAKE CONTROLS – MBE900 AND MBE4000
The Engine Brake option converts a power-producing diesel engine into a power-absorbing air
compressor. This is accomplished by opening the constant throttle valve over all cylinders near
the top of the normal compression stroke and releasing the compressed cylinder charge to exhaust.
The release of the compressed air to atmospheric pressure prevents the return of energy to the
engine piston on the expansion stroke, the effect being a net energy loss. Fueling is cut off when
this occurs. The constant throttle valves are open over all cycles, not just the exhaust cycle.
5.6.1

OPERATION

A dash mounted On/Off Switch is used to enable the Engine Brake option. Engine Brake
operations are allowed only when all of the following conditions are met:
□ Percent throttle <4%
□ Driveline open – engine speed >1100 rpm
□ Driveline closed – engine speed >800 rpm
□ Road Speed > 0 mph (programmable)
□ ABS not active
□ Clutch pedal released (if equipped)
□ Engine not fueling
□ Engine not in PTO mode
□ Torque converter locked up (automatic transmission)
If all of these conditions are met, engine brake can be activated when the engine brake switches
are on. Engine brakes will be deactivated when at least one of these conditions is no longer met
or the engine brake switch is turned back to the OFF position.
The following are features and options for Engine Brake:
□ Cruise Control or Road Speed Limit with Engine Brake
□ Engine Brake Disable
□ Engine Brake Active
□ Engine Fan Braking
□ Clutch Released Input
□ Service Brake Control of Engine Brakes
□ Min MPH for Engine Brakes
All information subject to change without notice. (Rev. 01/07)
7SA827 0701 Copyright © 2007 DETROIT DIESEL CORPORATION
DDEC VI ELECTRONIC CONTROLS APPLICATION AND INSTALLATION
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