EGR DIFFERENTIAL PRESSURE SENSOR ENGINE OIL PRESSURE (EOP) SENSOR The EGR differential pressure sensor is used for flow measurement of the Exhaust Gas Recirculation (EGR) valve. This sensor has two pressure ports and senses the difference in pressure between the two ports. Measurement of the pressure before and after the EGR valve is used to calculate EGR flow. The Engine Oil Pressure Sensor contains a pressure sensitive diaphragm and a electrical amplifier. Mechanical pressure applied to the diaphragm causes the diaphragm to deflect and the amplifier to produce an electrical signal proportional to the deflection. The Engine Oil Pressure Sensor is located on the oil filter assembly.
The sensor monitors engine oil pressure to warn of lubrication system failure. The EGR Differential Pressure Sensor is located on the left or right side of the engine. EGR TEMPERATURE SENSOR ENGINE OIL LEVEL (EOL) SENSOR The EGR temperature sensor detects exhaust gas temperature for EGR system. The sensor modifies a voltage signal from the control unit. The modified signal returns to the control unit as the exhaust temperature of the EGR system to confirm EGR operation. The sensor uses a thermistor that is sensitive to the change in temperature. The Engine Oil Level Sensor is located in the oil pan.
ENGINE OIL TEMPERATURE (EOT) SENSOR The Engine Oil Temperature Sensor is a thermistor whose resistance varies inversely to temperature. The sensor has a negative temperature coefficient, which means the sensor resistance will decrease as the engine oil temperature increases. The EGR Temperature Sensor is located near the EGR valve. ENGINE COOLANT LEVEL (ECL) SENSOR The Engine Oil Temperature Sensor is located in the oil pan. The Engine Coolant Level (ECL) Sensor is a switch. If engine coolant level falls below a calibrated point the contacts open and the driver will be notified of the low coolant level.
EXHAUST TEMPERATURE SENSOR (DPF SENSORS) The Engine Coolant Level (ECL) Sensor is located in the cooling system reservoir tank. The exhaust gas temperature sensor detects exhaust gas temperature for DPF protection as well as DPF regeneration control. The sensor modifies a voltage signal from the control unit. The modified signal returns to the control unit as the exhaust temperature at that specific location of the exhaust. The sensor uses a thermistor that is sensitive to the change in temperature. ENGINE COOLANT TEMPERATURE (ECT) SENSOR The Engine Coolant Temperature Sensor is located in the thermostat body at the front of the engine.
The sensor will indicate a high coolant temperature caused by problems like radiator blockage, thermostat failure, heavy load, or high ambient temperatures. This sensor is also used for cold start enhancement and for fan clutch engagement. The Exhaust Temperature Sensors are located in the DPF assembly. FILTER INLET THERMOCOUPLE (A3) This thermocouple is used to measure exhaust gas temperature at the inlet face of the DPF filter. The amount of fuel injected by the atomization module is metered based on the output of this thermocouple to meet the required temperature profile. The filter inlet thermocouple is located on the side of the DPF and is positioned before the DPF filter.
Page 9 DESCRIPTION AND OPERATION