General Information

On Board Diagnostic (OBD) Features
The Motronic Engine Control Module (ECM) -J220- is equipped with a DTC memory.

If Diagnostic Trouble Codes (DTCs) occur in the sensors and components being monitored, they will be stored in the DTC memory together with an indication of the type of malfunction.

After evaluating the information the Motronic Engine Control Module (ECM) -J220- decides between the different Diagnostic Trouble Codes (DTCs) DTC table from and stores these until the contents of the DTC memory are erased. SAE P0 Codes

Diagnostic Trouble Codes (DTCs) which only occur sporadically will have the addendum "sporadic fault" on the print out. These Diagnostic Trouble Codes (DTCs) will be indicated on the display by the addendum "/SP". The cause of sporadic Diagnostic Trouble Codes (DTCs) can be e.g. a loose terminal or a brief open circuit. If a "sporadic malfunction" does not occur again within 40 warm-up phases (engine start below 50 degrees C coolant temperature -switched off above 72 degrees C), it will be erased from the DTC memory.

The Diagnostic Trouble Codes (DTCs) stored can be read-out with the VAG 1551 scan tool, the vehicle system tester VAG 1552 or the vehicle diagnostic, testing and information system VAS 5051 Reading Diagnostic Trouble Codes

The DTC memory must be erased after the malfunction(s) have been repaired and the readiness code must be regenerated Reading Diagnostic Trouble Codes Monitors, Trips, Drive Cycles and Readiness Codes.

All Motronic Engine Control Module (ECM) -J220- learned values will be erased when the Motronic Engine Control Module (ECM) -J220- connector is pulled off or the battery is disconnected. However the contents of the DTC memory are retained. When the engine is subsequently started the idling could be rough for a brief period. In this case leave the engine running for a few minutes at idle or perform a longer road test, until the learning process is completed. Procedure after voltage supply has been interrupted. Testing and Inspection

NOTE: General information for On Board Diagnosis (OBD) can be found in the instruction manuals for the VAG 1551 scan tool, vehicle system tester VAG 1552 or VAS 5051.