On-Board or Off-Board Diagnostics

First of all, in this training, Diagnostics, you are going to learn the key differences between On-Board and Off-Board Diagnostics. What should we understand from both terms? By which mean and purpose do we need both applications? Self-Diagnosis of each ECU, reaction of the system, elimination of errors, diagnostic testing, documentation of diagnostics (ODX), implementing diagnostic services and of course diagnostic communication protocol: UDS (Unified Diagnostic Services).

ISO 14229-1:2013 specifies data link independent requirements of diagnostic services, which allow a diagnostic tester (client) to control diagnostic functions in an on-vehicle Electronic Control Unit (ECU, server) such as an electronic fuel injection, automatic gear box, anti-lock braking system, etc. connected to a serial data link embedded in a road vehicle.

It specifies generic services, which allow the diagnostic tester (client) to stop or to resume non-diagnostic message transmission on the data link.

Road vehicles – Unified diagnostic services (UDS)

 

Diagnostics – Content

• Overview: Diagnostics
• Standard Definitions (i.e. DTC – Diagnostic Trouble Code)
• On-Board versus Off-Board Diagnostics
• A Communication Protocol for Diagnostic Testing: UDS (Unified Diagnostics Services)
• Transport protocols: CAN vs Flexray
• Implementation of Diagnostic Services
• Benefits of ODX Exchange: A special standardized description file that supplies all needed diagnostic information and enables to exchange information between OEMs and Suppliers
• Development and Diagnostic Testing with an or more ECU(s)
• Examples
• AUTOSAR and Diagnostic-specific BSWs (Basic Software):
  • DCM: Diagnostic Communication Manager
  • DEM: Diagnostic Event Manager
  • FIM: Function Inhibition Manager
• On-Board Diagnostic II Certification and Documentation