9 Apparatus for testing vehicle engines, namely, hardware and software for testing diesel-engine On-Board Diagnostic (OBD) behavior; built-in apparatus for testing vehicle engines, namely, hardware and software for testing diesel-engine On-Board Diagnostic (OBD) behavior; workshop service tester, namely, hardware and software for error memory management and reprogramming of vehicle electronic control units, and guided fault finding; devices for diagnosing faults and fault analysis devices for vehicles, namely, hardware and software for the diagnostic communication with electronic control units for heavy-duty applications, such as heavy-duty diesel engines, diesel particulate filters, and selective catalytic reduction systems; test apparatus for fault location in vehicle engines, namely, hardware and software for the diagnostic communication with electronic control units for heavy-duty applications, such as heavy-duty diesel engines, diesel particulate filters, and selective catalytic reduction systems; testing apparatus and diagnostic apparatus not for medical purposes, namely, hardware and software for the diagnostic communication with electronic control units for heavy-duty applications, such as heavy-duty diesel engines, diesel particulate filters, and selective catalytic reduction systems; measuring and control apparatus and instruments, namely, modules for the measurement of physical values, namely, measurement amplifier for measuring voltage and for measuring current using shunts, measurement amplifier for acquiring voltage-fed transducers, measurement amplifier for supplying and acquiring ratiometric transducers, measurement amplifier for temporal interpretation of pulse-shaped signals, measurement amplifiers for measuring temperatures with thermocouples of the type K, output module for generating analog voltage signals, input and output module for acquiring and generating digital signals; computer programs and software for automotive external test equipment, based on SAE and ISO standards; data processing devices and computers; computer hardware; apparatus and devices for data collection and storage, namely, VCIs (Vehicle Communication Interfaces), data logger; data communication software and devices, namely, VCIs with application programming interfaces