On-board diagnostic systems in wheeled tractors

Periodic inspections in service stations do not always deliver optimal results due to limited service time, restricted scope of the inspection and the absence of working load during the diagnostic process. Diagnostic systems in modern wheeled tractors do not make full use of the relations between diagnostic symptoms and parameters. Damaged components in a given assembly are not specifically identified. The diagnostic system for a wheeled tractor determines a tractor's operating parameters based on fuel consumption data, and the identified defects are classified into several groups in view of the consequences they produce: functional defects (uf), exhaust defects (ue), defects that jeopardize driving safety (us) and defects that affect engine performance (ud). A series of diagnostic procedures were developed for the needs of an OBD system in a wheeled tractor. The results of tractor trials indicate that significant mechanical defects lead to changes in various diagnostic parameters. For this reason, a wide range of diagnostic parameters should be analyzed by an OBD system to reliably identify defects and minimize the risk of an incorrect diagnosis. This paper presents an on-board diagnostic system developed at the University of Warmia and Mazury in Olsztyn and the Gdańsk University of Technology. Trial results revealed that the analyzed OBD system is capable of detecting a wide range of tractor defects in real time.