3B2-83880-2 Tohatsu S.R.C. FITTING PARTS ASSY

Illustration 1 g00885458
Top view (1) Injection actuation pressure control valve. (2) Oil temperature sensor. (3) Coolant level sensor. (4) Oil pressure sensor. (5) Secondary speed/timing sensor. (6) Atmospheric pressure sensor. (7) Fuel temperature sensor. (8) Primary speed/timing sensor. (9) Coolant temperature sensor. (10) Turbocharger outlet pressure sensor. 9KS and 9PW. (11) Injection actuation pressure sensor. (12) Turbocharger outlet pressure sensor (S/N: CLX). (13) Inlet air temperature sensor. (S/N: CLX)
Illustration 2 g00541881
Detail A (1) Injector actuation pressure control valve. (2) Oil temperature sensor. (4) Oil pressure sensor. (5) Secondary speed/timing sensor.
Illustration 3 g00541846
Right side view (12) Fuel pressure sensor. (13) Control panel connectors, "P94" and "J107".
Illustration 4 g00541850
Left side view (12) Fuel pressure sensor. (13) Control panel connectors, "P94" and "J107".
Illustration 5 g00541888
Rear view (14) Data booster. (15) Top dead center probe connector "(P26)". (16) ECM connector "P1". (17) ECM connector "P2".
Illustration 6 g00541890
Section B-B (14) Data booster. (18) Service tool connector "(J60)". (19) Customer connector "(J3)".The electronic control system is integrally designed into the engine's fuel system and the engine's air inlet and exhaust system in order to electronically control the fuel delivery. The electronic control system provides better timing control and fuel air ratio control in comparison to conventional mechanical engines. Injection timing is achieved by the precise control of the fuel injectors. Engine speed is controlled by adjusting the injection duration. The Electronic Control Module (ECM) energizes the unit injector solenoids in order to start the injection of fuel. Also, the ECM de-energizes the unit injector solenoids in order to stop the injection of fuel. Refer to Systems Operation/Testing And Adjusting, "HEUI Injector Operation" for a complete explanation of the fuel injection process.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. The signal that is sent varies in either of the following ways:
voltage
frequency
pulse widthThe variation of the signal is in response to a change in some specific system of the engine. Some specific examples of an input component are the engine speed-timing sensors, and the coolant temperature sensor. The 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 electrical energy to make an adjustment in one of the engine's systems. An output component may also provide information to the operator.As an example, a moving solenoid plunger will perform work. By performing work, the component has functioned in order to regulate the engine.As an example, a control 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 data to the ECM. The following sensors are used by the ECM for data:
engine coolant temperature
boost pressure
engine oil temperature
engine oil pressure
engine speed
atmospheric pressure
injection actuation pressure
fuel temperature
fuel pressure
inlet air temperatureThe ECM processes the data. Then, the ECM sends an electronic signal to the fuel injector. The signal will control the amount of fuel that is injected into the cylinder. This will optimize the efficiency and the performance of the engine.Data Link
A data link is used for the following items:
communicate engine information.
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 monitors engine information. The Data Link is used to communicate engine information to other electronic control systems. Also, the Data Link can interface with Caterpillar service tools.The Electronic Technician (ET) or the Electronic Control Analyzer Programmer (ECAP) is used to program the customer specified parameters.The ET 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 ET can be used to display the real time values of all information that is available on the Data Link. This will help diagnose engine problems.System Diagnostic Codes
Electrical Connectors And Functions
Table 1
Electrical Connectors And Functions    
Jack/Plug No.     Connector    
J1/P1     ECM    
J2/P2     ECM    
J3/P3     Customer Connector (40 pin)