You probably didn't now that car parking sensors are one of the most sensitive sensors installed at vehicle. Environmental exposure (rain, dust, temperature), mechanical impacts (shocks at bumper in case off accident, parking failures, ...), degradation during time, aging, ... are just few reasons why car parking sensors could fail. Many times sensors are not failing completely and they are working but non-properly and car drivers actually don't know that sensors are not showing correct parking distance. In many cases also sensor wiring could be an issue with bad contacts or damaged wirings. This is usually causing voltage drop at sensor site and sensor is not able to create efficient sound wave anymore. Diagnosis of car parking sensors usually requires car brand specific diagnosis tool which could show real-time distance readings from each sensor but also these kind of information could not be 100% reliable. Car parking sensors are transmitting pulses at standardised frequencies (40KHz, 48KHz, 58KHz) in waves (PINGs) where partially failed sensors could omit some pulses which causes that reflected waves are not correct and this particular sensor will cause distance measure error. PDCTESTER tool is continuously analysing transmitted pulses from the sensor and is processing last second of pulses and with continuous beeping it is indicating proper operation of each particular sensor being tested. In case of pulses being lost beeping is intermitted to indicate that operation of this sensor is not correct. If sensor is working 100% properly PDCTESTER tool is beeping continuously without any interruption. In this case all sensors should beep with same frequency and same volume. If sensor is damaged or there is a wiring or contact related problem PDCTESTER is not beeping continuously or beeping volume differs between sensors. If OEM sensor is replaced with non-OEM this could result in different excitation frequency, for instance 58KHZ could be replaced with 40KHz which could cause an error in operation and could be very quickly discovered by PDCTESTER tool. PDCTESTER tool is a universal tool compatible with all car brands because it detects 3 different sensor's ultrasonic frequencies which could be found in different cars on the market. PDCTESTER could save many repair costs in terms off labour and material, because it could indicate failure at each particular sensor even without car dismantle (bumper removal, ...) or special diagnosis tool connection.