Audi Q7: Communication

 Engine Component Power Supply Relay - J757-, Checking

General Description The following procedure is used to diagnose the Engine Component Power Supply Relay -J757- and the power supply voltage that is provided to the engine components. Special tools and workshop equipment required Multimeter. Wiring Diagram. Scan Tool. Test requirements Fuse

 On Board Diagnostic Systems

On Board Diagnostics, or OBD, is an automotive term referring to a vehicle's self-diagnostic and reporting capability. OBD systems give the vehicle owner or repair technician access to the status of the various vehicle sub-systems. Modern OBD implementations use a standardized digital communica