The Pico Technology Ultrasonic Parking Sensor Detector, No. TA329, is designed to make testing a vehicle's proximity sensors quick and easy. According to the company, this detector picks up ultrasonic signals in its immediate vicinity. The sensor's 6.5' lead and detector wand convert high-frequency pulses into voltage a scope can display. Technicians can then calculate the strength, frequency and duration of each sensor's signal or compare the signals of multiple sensors to confirm suspected failures.