822844 1 Mercury GASKET

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Right side view (1) Electronic control module (ECM) (2) Rack position sensor (3) Boost pressure sensor (4) Coolant temperature sensor (5) Engine oil pressure sensor (6) Atmospheric pressure sensor (7) Speed sensor (8) Speed sensor
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View A-A (9) Fuel shutoff solenoid (10) Rack solenoid (BTM) (11) ATA data linkThe electronic control system is designed into the engine's fuel system. The system is designed to electronically control the delivery of fuel and injection timing.The engine uses the following three types of electronic components:
input component
control component
output componentAn input component is one that sends an electrical signal to the ECM of the system. The signal that is sent varies in either of the following ways:
voltage
frequencyThe ECM interprets the signal from the input component as information about the condition, environment, or operation of the engine.A control component (ECM) receives the input signals from the input components. Electronic circuits inside the control component evaluate the signals from the input components. These electronic circuits also supply electrical energy to the output components of the system. The electrical energy that is supplied to the output components is based on predetermined combinations of input signal values.An output component is one that is operated by a control module. The output component receives electrical energy from the control group. The output component uses that electrical energy in one of two ways. The output component can use that electrical energy in order to perform work. As an example, a moving solenoid plunger will perform work. The output component can use that electrical energy in order to provide information. As an example, a dash panel light or an alarm will provide information to the operator of the engine.These electronic components provide the ability to electronically control the engine operation. Engines with electronic controls offer the following advantages:
improvement in performance
improvement in fuel consumption
reduction in emissions levelsVarious sensors feed engine data to the ECM. These sensors modify the following functions:
boost pressure
engine oil pressure
engine speed
fuel rack position
throttle position
on/off ignitionThe ECM processes the data. Then, the ECM sends electronic signals to the fuel injection solenoids. The fuel injection solenoids move the fuel rack. This will optimize the efficiency and the performance of the engine.The electronic engine control system also has the following built-in functions:
engine overspeed
on board diagnosticsData Link
A data link is used for the following items:
communicate the information from the engine.
communicate with Caterpillar service tools.
calibrate the electronic engine control system.
troubleshoot the electronic engine control system.
program the electronic engine control system.The electronic engine control system includes a Data Link. The Data Link communicates with other microprocessor based devices. These devices are compatible with SAE Recommended Practices J1708 and J1587. The Data Link can reduce the duplication of sensors by allowing the controls to share information.The Data Link is used to communicate engine information to other electronic control systems. The Data Link can interface with Caterpillar service tools such as the Electronic Control Analyzer Programmer (ECAP).The Data Link monitors engine information. The engine information that is available on the Data Link includes the following information:
boost pressure
engine identification
engine speed
oil pressure
rack position
status and diagnostic information
throttle positionThe Electronic Control Analyzer Programmer (ECAP) is used to program the customer specified parameters.The ECAP is one method of programming the customer specified parameters that are selected by the customer. The tool plugs into the Data Link Connector. This allows the tool to communicate with the ECM. Also, the ECAP can be used to display the real time values of all the information that is available on the Data Link. This will help diagnose engine problems.System Diagnostic Codes
Table 1
Diagnostic Flash Codes    
Flash Code     Description of Code    
21     Sensor Supply Voltage Fault    
22     Rack Position Sensor Fault    
24     Oil Pressure Sensor Fault    
25     Boost Pressure Sensor Fault    
26     Atmospheric Pressure Sensor Fault    
27     Coolant Temperature Sensor Fault    
32     Throttle Position Sensor Fault    
33     Engine RPM Signal Fault    
34     Loss Of Engine Speed Signal    
35     Engine Overspeed Warning    
42     Check the Boost Sensor Calibration    
43     Rack Subsystem Fault    
45     Shutoff Solenoid Fault    
46     Low Engine Oil Pressure Warning    
48     Excessive Engine Power    
51     Intermittent Battery Power to ECM    
52     ECM or Personality Module Fault    
53     ECM Fault    
55     No Detected Faults    
56     Check Customer or System Parameters    
61     High Coolant Temperature Warning    
62     Low Coolant Temperature Warning    Refer to Electronic Troubleshooting Guide for a complete explanation of the Diagnostic Codes.Electronic Control Module (ECM) And Personality Module
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ECM and personality module (1) Electronic Control Module (ECM) (2) Fuel outlet (3) Fuel inlet (4) Personality moduleThe 3412C Generator Set Engine uses an ECM microprocessor. The ECM is mounted on the