This paper describes the development and the verification of the "probe system" which estimates the track conditions without sensors on bogie. To detect the track conditions from the data which can be observed in the interior of a service vehicle, two methods have been proposed: the method to detect track irregularities using RMS of the lateral/vertical accelerations and the rolling of the vehicle body, and the method to detect rail corrugations from the interior noise using the windowed Furrier transform. Video recording function was added to use probe system as Drive recorder function by image. The developed system has been installed onto the cab of a service vehicle to carry out a field test for the validation of the system. As a result of the experiment, Video recording function showed that it became the function improvement of probe system.