EGR Temperature Sensor

EGR temperature sensor, located near EGR valve, detects temperature of exhaust gases passing through EGR valve. Sensor has a thermistor which changes its resistance value in response to EGR flow. As temperature increases, resistance of sensor decreases. If absence of EGR flow is detected when PCM calls for EGR operation, a low flow fault is set in PCM memory. If EGR flow is detected during no flow conditions, a high flow fault is set in PCM memory.