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General Information




On Board Diagnostic (OBD) of Motronic system

Technical data for On Board Diagnostic

Equipment

The term "OBD" relates specifically to the electrical and electronic part of the control system.

The control unit is equipped with a Diagnostic Trouble Code (DTC) memory so that the malfunction can be traced quickly in the event of an electronic/electrical component failure or an open circuit.

The advantages of OBD can only be fully exploited by using the Vehicle Diagnostic, Testing and Information System VAS 5051 or the VAG 1551 Scan Tool, in operating mode 1 "Rapid data transfer."

For functions which can be identified by the Vehicle Diagnostic, Testing and Information System VAS 5051 and the VAG 1551 Scan Tool can be identified, list of available functions.

The DTC memory is equipped with a permanent memory and therefore does not depend on the power supply.


NOTE:
- Every time the DTC memory is erased the readiness code must be generated, Readiness Code Reading
- The Exhaust Malfunction Indicator Light (MIL) in the instrument cluster will be switched on if the engine control module recognizes malfunctions which have an affect on exhaust emissions, Malfunction Indicator Lamp (MIL)
- Malfunctions relating to the electronic throttle are also indicated by a Electronic Power Control (EPC) malfunction indicator light in the instrument cluster, Refer to "Significance of electronic Engine Power Control (EPC) malfunction indicator light in instrument panel" under Instrument Panel,Gauges and Warning Indicators Testing and Inspection