BOLT 5P0233 - Caterpillar

Sensor Locations
The Illustration within the section shows the typical locations of the sensors for a C7.1 Industrial Engine. Specific engines may appear different from the illustration due to differences in applications.
Illustration 1 g02150593
(1) Engine Intake Throttle Valve
(2) Wastegate Regulator
(3) Control Valve for the NOx Reduction System (NRS)
(4) Temperature Sensor for the NOx Reduction System
(5) Intake Pressure Sensor for the NOx Reduction System (NRS)
(6) Differential Pressure Sensor for the NOx Reduction System (NRS)
(7) Fuel Pressure Sensor (Fuel Rail Pressure Sensor)
(8) Intake Manifold Air Temperature Sensor
(9) Intake Manifold Pressure Sensor
(10) Electronic Control Module (ECM)
(11) Atmospheric Pressure Sensor (Barometric Pressure Sensor)
(12) Primary Speed/Timing Sensor
(13) Starting Motor
(14) Oil Pressure Sensor
(15) Oil level Switch ( if Equipped)
(16) Diagnostic Connector
(17) Fuel Temperature Sensor
(18) Solenoid for the High Pressure Fuel Pump
(19) Coolant Temperature Sensor
Illustration 2 g02150594
The location of the fuel filters will depend on the application.
(20) Differential Pressure Switch for the Secondary Fuel Filter
(21) Water in Fuel Switch
(22) Secondary Speed/Timing Sensor
(23) Fuel Priming Pump
(24) Alternator
(25) Refrigerant Compressor (if equipped)
Illustration 3 g02151173
(1) Engine Intake Throttle Valve
(2) Wastegate Regulator
(3) Control Valve for the NRS
(4) Temperature Sensor for the NRS
(5) Intake Pressure Sensor for the NRS
(6) Differential Pressure Sensor for the NRS
(7) Fuel Pressure Sensor (Fuel Rail Pressure Sensor)
(8) Intake Manifold Air Temperature Sensor
(9) Intake Manifold Pressure Sensor
Illustration 4 g02151174
(10) Electronic Control Module (ECM)
(11) Atmospheric Pressure Sensor (Barometric Pressure Sensor)
(12) Primary Speed/Timing Sensor
(13) Starting Motor
(14) Oil Pressure Sensor
(15) Oil Level Switch (if Equipped) The oil level switch (15) will only operate with the application on level ground and the power in the ON position. The engine must be at zero RPM. A coolant level switch can be installed, this switch only operates at key on, and the application must be on level ground.
Illustration 5 g02151327
(16) Diagnostic Connector
(17) Fuel Temperature Sensor
(18) Solenoid for the High Pressure Fuel Pump
(19) Coolant Temperature Sensor
Illustration 6 g02151177
(20) Differential Pressure Switch for the Secondary Fuel Filter
(21) Water in Fuel Switch
(22) Secondary Speed/Timing Sensor
(23) Fuel Priming Pump Programmable Monitoring System (PMS)
The Programmable Monitoring System determines the level of action that is taken by the Engine Control Module (ECM) (10). In response to a condition that can damage the engine. These conditions are identified by the ECM from the signals that are produced from the following sensors.
Coolant Temperature Sensor
Intake Manifold Air Temperature Sensor
Intake Manifold Pressure Sensor
Fuel Pressure Sensor
Engine Oil Pressure Sensor
Primary Speed/Timing Sensor
Secondary Speed/Timing Sensor
Fuel Temperature Sensor
Temperature Sensor for the NRS
Intake Pressure Sensor for the NRS
Differential Pressure Sensor for the NRS