SWITCH BOX ASS 0878476 - Caterpillar

Illustration 1 g03717266
Rear of Engine (1) Coolant temperature sensorCoolant temperature sensor (1) is located on the rear of the engine.Coolant temperature sensor (1) provides input signals to the engine ECM. The engine ECM calculates the correct fan speed factoring this temperature measurement with signals from the following sensors:
Intake manifold temperature sensor
Generator oil temperature sensor
Hydraulic oil temperature sensorThe engine ECM applies a signal to the fan control solenoid to achieve proper cooling for the current operating conditions.
Illustration 2 g03717861
Rear of Engine (2) Intake manifold temperature sensorIntake manifold temperature sensor (2) is located on the rear side of the engine. The top engine compartment door provides limited access to this component.Intake manifold temperature sensor (2) measures intake air temperature after the air has been cooled by the air-to-air-after-cooler (ATAAC). This sensor provides an input signal to the engine ECM. The ECM uses the input signal in the fan control logic.
Illustration 3 g03717866
Right Side of Machine (3) Generator oil temperature sensorGenerator oil temperature sensor (3) is located in the generator sump, below the right side of the engine. This component is accessed through the right hopper door.Generator oil temperature sensor (3) is an analog resistive sensor. The machine ECM monitors this sensor and reports the sensor data to the engine ECM through the CAN bus.
Illustration 4 g03717867
Hydraulic Tank Graphic (4) Hydraulic oil temperature senderHydraulic oil temperature sender (4) is installed in the front side of the hydraulic tank. The hydraulic tank is located under the operator platform.Hydraulic oil temperature sender (4) is a resistance-type device. The machine ECM measures the resistance through the sender to determine the hydraulic oil temperature. This information is sent to the engine ECM through the CAN bus. The hydraulic oil temperature measurement is one of the parameters the engine ECM uses to calculate the correct fan speed.
Illustration 5 g03717893
Engine Compartment (5) Cooling fans (6) Cooling packageCooling package (6) is located below cooling fans (5). The engine compartment cover at the front of the machine provides access to the components of the cooling package. Cooling package (6) contains the following components of the fan system:
Air-to-air aftercooler
Radiator
Hydraulic oil cooler
Integrated generator cooler
Fuel coolerCooling fans (5) counter-rotate. Cool air is drawn in from the outside of the machine and pulled across the cooling package. The air then exits toward the front of the machine.