3801745 Volvo.Penta Cylinder head, exch

Electronic Controls
The electronic system consists of the following components: the ECM, the electronic unit injectors (EUI), the wiring harnesses, the switches and the sensors. The ECM is the computer. The personality module is the software for the computer. The personality module contains the operating mapsthat define the following characteristics of the engine:
Horsepower
Torque curvesThe ECM determines the timing and the amount of fuel that is delivered to the cylinders. These decisions are based on the actual conditions and/or on the desired conditions at any given time.The ECM compares the desired engine speed to the actual engine speed. The actual engine speed is determined through the engine speed/timing sensor. The desired engine speed is determined through the following items:
Throttle signal
Other input signals from sensors
Certain diagnostic codesIf the desired engine speed is greater than the actual engine speed, the ECM injects more fuel in order to increase the actual engine speed.Fuel Injection
The ECM controls the amount of fuel that is injected by varying the signals to the injector solenoids. The injectors will pump fuel only if the injector solenoid is energized. The ECM sends a 105 volt signal to the injector solenoid. By controlling the timing and the duration of the high voltage signal, the ECM can control injection timing and the ECM can control the amount of fuel that is injected.The ECM limits engine power during "Cold Mode" operation and the ECM modifies injection timing during "Cold Mode" operation. "Cold Mode" operation provides the following benefits:
Increased cold weather starting capability
Reduced warm-up time
Reduced white smoke"Cold Mode" is activated whenever the engine's coolant temperature falls below a predetermined value. "Cold Mode" remains active until the engine's coolant temperature rises above a predetermined value.The personality module inside the ECM sets certain limits on the amount of fuel that can be injected. The Fuel Ratio Control (FRC) is used to control the air/fuel ratio for control of emissions. The FRC is a limit that is based on the turbocharger outlet pressure. A higher turbocharger outlet pressure indicates that there is more air in the cylinder. When the ECM senses a higher turbocharger outlet pressure, the ECM increases the FRC. When the ECM increases the FRC, the ECM allows more fuel into the cylinder. The FRC is programmed into the personality module at the factory. The FRC cannot be changed.The rated fuel position is a limit that is based on the power rating of the engine. The rated fuel position is similar to the rack stops and to the torque spring on a mechanically governed engine. The rated fuel position limits the power curves and the torque curves for a specific engine family and for a specific engine rating. The rated fuel limit is programmed into the personality module at the factory. The rated fuel limit cannot be changed.Once the ECM determines the amount of fuel that is required, the ECM must determine the timing of the fuel injection. The ECM determines the top center position of each cylinder from the engine speed/timing sensor's signal. The ECM decides when fuel injection should occur relative to the top center position and the ECM provides the signal to the injector solenoid at the desired time. The ECM adjusts timing for optimum engine performance, for optimum fuel economy, and for optimum control of white smoke.Engine Wiring Diagram for the 3500B Engine with CMS and Without 2301A Loadshare
Illustration 1 g00638234
Engine Wiring Diagram for the 3500B Engine with EMCP II and 2301A Loadshare
Illustration 2 g00638235
Location Of The Engine Components
Illustration 3 g01019347
Typical left side view (1) Connector for the electronic unit injector (2) Left exhaust temperature sensor (3) Air shutoff (4) Left turbocharger compressor inlet pressure sensor (5) Ether starting aid (6) Electric starting motor (7) Engine speed/timing sensorLocation Of The Engine Components
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Typical left side view of section A (8) Unfiltered fuel pressure sensor (9) Filtered fuel pressure sensor (10) Filtered engine oil pressure sensor (11) Coolant temperature sensor (12) Atmospheric pressure sensor (13) Aftercooler temperature sensorLocation Of The Engine Components
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Typical right side view (14) Right turbocharger compressor inlet pressure sensor (3) Air shutoff (15) Right exhaust temperature sensor (16) Air start solenoid (17) Crankcase pressure sensor (18) Instrument panel connector (19) Electronic service tool connector J60/P60 (20) Prelube pump (21) AlternatorLocation Of The Engine Components
Illustration 6 g01019352
Typical front view (14) Right turbocharger compressor inlet pressure sensor (10) Filtered engine oil pressure sensor (3) Air shutoff (4) Left turbocharger compressor inlet pressure sensor (22) Unfiltered engine oil pressure sensor (23) Instrument panel (24) Turbocharger compressor outlet pressure sensor (25) ECM (13) Aftercooler temperature sensorLocation Of The Engine Components
S