3AB-05003-0 Tohatsu RATCHET

Illustration 1 g01386870
Left side engine view (typical configuration)
(1) Throttle actuator
(2) Exhaust temperature module
(3) Interface box
(4) Electronic Control Module (ECM)
(5) Actuator for the fuel valve
(6) Fuel valve Throttle Actuator
Throttle actuator (1) is electronically controlled and electrically actuated. The ECM issues a throttle command to the throttle actuator via the CAN data link. The command can be viewed on the Caterpillar Electronic Technician (ET).Exhaust Temperature Module
The exhaust temperature module (2) is an electronic scanner for exhaust temperatures. The module monitors the following thermocouples:
Thermocouples for each exhaust port
Thermocouples at the inlet of each turbocharger
Thermocouples at the outlet of each turbochargerThe module displays the temperatures. The exhaust temperature module also sends the temperatures via the CAN data link to the engine ECM and the optional remote control panel for display. The exhaust temperature module has two switches that can be wired to alarms or to relays. Refer to Systems Operation Testing and Adjusting, KENR5473, "Exhaust Temperature Module" for additional information.Interface Box
Interface box (3) contains the fuses for the engine. An emergency stop button is provided on the front face of the box. The box provides a water tight enclosure for connecting the following items:
Wiring from the electrical power supply
Wiring from the alternator (if equipped)
Connections from the driven equipmentECM
ECM (4) controls most of the functions of the engine. Refer to Troubleshooting, "System Overview" for additional information on the ECM.Fuel Actuator
Optional fuel actuator (5) is electronically controlled and electrically actuated. The ECM issues a fuel command to the fuel actuator via the CAN data link. The command can be viewed on Cat ET.Fuel Valve
Optional fuel valve (6) is a mechanical valve that controls the amount of fuel. Mechanical linkage that connects the valve to the fuel actuatorSensors
Illustration 2 g01386871
Front engine view (typical configuration)
(7) Inlet air temperature sensor
(8) Engine coolant temperature sensor
(9) Coolant pressure sensor at the outlet of the coolant pump
(10) Sensor for the unfiltered engine oil pressure
(11) Sensor for the filtered engine oil pressure
(12) Inlet air pressure sensor
(13) Oil temperature sensor
Illustration 3 g01387128
Left rear engine view (typical configuration)
(14) Thermocouples for engine exhaust temperatures
(15) Oxygen sensor or NOx sensor (if equipped)
(16) Buffer for the oxygen sensor (if equipped) or the buffer for the NOx sensor (if equipped)
(17) Emergency stop button
(18) Engine speed/timing sensor
Illustration 4 g01387441
Right side view
(19) Solenoid for air start
(20) Coolant pressure switch at the inlet of the engine block
(21) Solenoid for prelubrication (if equipped)
(22) Detonation sensor for the right cylinder bank
Illustration 5 g01395774
Left rear view
(23) Detonation sensor for the left cylinder bank
(24) Prelubrication pressure switch Sensors provide information to the ECM. The information enables the ECM to control the engine as efficiently as possible over a wide range of operating conditions. The information is also used for monitoring engine operation. The ECM uses the information from the sensors in order to activate alarms or shutoffs in response to abnormal operation. Illustrations 2, 3, and 4 show the locations of the sensors for the engine. Refer to Systems Operation/Testing and Adjusting, "Engine Sensors" for the descriptions of the sensors.Remote Panel
Illustration 6 g01387444
Remote panel
(25) Advisor monitor display
(26) Manual prelubrication switch and indicator
(27) Emergency stop button
(28) Engine control
(29) Desired speed potentiometer