MBE 4000 SERVICE MANUAL From these data, instructions are computed for controlling the engine and transmitted to the DDEC-ECU via the proprietary datalink. The DDEC-VCU controls various systems, for example, communications with the datalink, the engine brake, and the constant-throttle valves. If the engine control system detects a fault, the appropriate fault code is broadcast on the datalink and can be read using minidiag2. When there is a fault, the code for the control unit reporting the fault can be read directly on the display.
ENGINE BRAKING POWER Exhaust Brake/Constant-Throttle Valves To increase braking performance, the engine is equipped with an exhaust brake on the turbocharger in conjunction with constant-throttle valves on the cylinder head. NOTE: The constant-throttle values are activated by engine oil pressure. The exhaust back-pressure is used by the exhaust brake to increase braking performance. Optional Turbo Brake For high braking output, the MBE 4000 engine can be equipped with an optional turbo brake. The turbo brake increases the air mass flow through the engine to provide up to 600 brake horsepower.
The turbo brake can be operated either manually or automatically, through the cruise control function. Because the charge air pressure is maintained at a high level during braking, full throttle response is available immediately, if the operator desires it, without any turbo lag. The turbo brake is maintenance-free, highly reliable, and adds virtually no weight to the engine. GENERAL SPECIFICATIONS AND ENGINE VIEWS For a general view of the MBE 4000 engine, showing major components, see Figure 3 for the left-hand side, and see Figure 4 for the right-hand side.
For a general view of the MBE 4000 engine, showing ports and fluid lines, see Figure 5 for the left-hand side and see Figure 6 for the right-hand side. For a general view of the MBE 4000 engine, showing sensor locations, see Figure 7. Two sensors are not easily visible from the left-hand side of the engine: the charge pressure/temperature sensor, located on the right-hand side of the charge air manifold, and the oil pressure/temperature sensor located at the base of the oil filter. All information subject to change without notice. 6SE412 0403 Copyright © 2004 DETROIT DIESEL CORPORATION 7