GENERATOR GP 1473331 - Caterpillar

Pulse width modulated sensors (PWM) produce a digital signal with a duty cycle that varies as the condition changes. The frequency remains constant. Temperature Sensor - Fluids And Ambient Air
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Fluid Temperature Sensor (1) Schematic symbol (2) SensorTemperature sensor (2) reacts to the temperature of fluids such as hydraulic oil, power train oil, or engine coolant. The sensor receives operating power from the VIMS interface module. The sensor sends a signal that changes as the fluid temperature changes to the main module. The VIMS measures the duty cycle of the sensor signal in order to determine the fluid temperature. Temperature Sensor - Engine Exhaust Gas
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Engine Exhaust Gas Temperature Sensor (1) Schematic symbol (2) SensorTemperature sensor (2) reacts to the temperature of engine exhaust gas. The sensor receives operating power from the VIMS interface module. The sensor sends a PWM signal which changes as the temperature of the engine exhaust gas changes to the main module. The control measures the duty cycle of the sensor signal in order to determine the temperature. Pressure Sensor
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Pressure Sensor (1) Schematic symbol (2) SensorPressure sensor (2) reacts to system pressure such as system air pressure. The sensor receives operating power from the appropriate interface module. The sensor sends a PWM signal to the VIMS that changes in proportion to the air pressure. The VIMS measures the duty cycle of the sensor signal in order to determine the pressure. Coolant Loss Sensor
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Coolant Loss Sensor (1) Sensor (2) Schematic symbol (3) Plastic sleeveThe coolant loss sensor is an electronic switch that is activated by coolant. During normal operation, coolant loss sensor (1) is closed to ground. The switch opens when the coolant level is too low. The VIMS module warns the operator of a very low coolant condition in the cooling system when the switch opens. The sensor has a connector with three contacts. Contact "A" connects to the +8 DCV sensor power from the interface module. Contact "B" connects to ground and contact "C" (switch output) connects to the input of the interface module. When the sensor is tested on the bench, the switch is open when power and ground are disconnected. The sensor cannot be tested in this state. Note: DO NOT remove plastic sleeve (3) from the probe. This plastic sleeve is required for proper switch operation. The internal electronic switch that is in this sensor functions as a mechanical switch. The switch is either open or the switch is closed to ground. Contact C is closed to contact B. This sensor works with ONLY water or water/glycol solutions (antifreeze). The sensor will not work with oils, fuels, etc. A pull-up voltage must be present at the signal lead. The pull-up voltage is used in order to pull up the open circuit voltage, when a loss of coolant has caused the switch to open. This pull-up voltage (5 VDC) is supplied by the interface module. The pull-up voltage can only be measured with a multimeter when the switch is