GASKET 3833689 - Caterpillar

The engine is designed for electronic control of most engine operating functions. The electronic system consists of an Electronic Control Module (ECM), wiring harness, switches, sensors, and Electronic Unit Injectors. The ECM monitors parameters during engine operation. The ECM supplies signals to the Electronic Unit Injectors. The ECM signals control the engine operation. Electronic Controls
Electronic Control Module
The ECM consists of two main components, the control computer (hardware) and the Personality Module (software). The control computer consists of a microprocessor and electronic circuitry. The Personality Module is the software for the control computer which contains operating maps that define power and torque curves.The ECM governs engine speed. Desired engine rpm is determined by the throttle position sensor signal and certain sensor readings. Diagnostic codes may derate the engine. Actual engine rpm is determined by the Engine Speed/Timing signal.Fuel Injection
The ECM controls the timing of the injectors. The ECM varies the signals to the injectors. Fuel is injected ONLY while an injector solenoid is energized by a 105 volt signal from the ECM. By controlling the timing and duration of the 105 volt signal, the ECM controls the fuel injection timing, the quantity of fuel and the desired engine rpm.Injection timing depends on engine rpm, load, and other operational factors. The ECM detects the top center of each cylinder. The ECM sends an injection signal at the desired time. The ECM limits engine power during cold mode operation. The ECM modifies the injection timing and the ECM cuts out the cylinders. This will increase startability and this will reduce warm up time. Cold Mode is activated whenever the engine coolant temperature falls below a predetermined value. Cold Mode remains active until the engine has warmed or a time limit is exceeded. The ECM is programmed at the factory which limits the quantity of fuel that can be injected. The FRC Fuel Position controls the fuel limit for exhaust smoke. The FRC is based on the maximum allowable fuel to air ratio.The FRC Fuel Position is increased when the ECM senses a higher Turbocharger Compressor Outlet Pressure. This will allow more fuel into the cylinder. The Rated Fuel Position is a limit that is based on the engine power rating. This is similar to the rack stops and the torque spring on a mechanically governed engine. The Rated Fuel Position provides power. The Rated Fuel Position provides the power curves and the torque curves for a specific engine family.Engine Wiring Diagram
Illustration 1 g00606460
Location of the Engine Sensors
Illustration 2 g00844954
Left side view 3508B (1) Unfiltered fuel pressure sensor (2) Filtered fuel pressure sensor (3) Filtered oil pressure sensor (4) Coolant temperature sensor (5) Left air shutoff valve (6) Left exhaust temperature sensor (7) Atmospheric pressure sensor (8) Aftercooler temperature sensor (9) Primary engine speed/timing sensor (10) Secondary engine speed/timing sensorLocation of the Engine Sensors
Illustration 3 g00844955
Right side view 3508B (11) Right exhaust temperature sensor (12) Crankcase pressure sensor (13) Right air shutoff valve (14) Timing calibration sensorLocation of the Engine Sensors
Illustration 4 g00606465
Front view 3508B (16)