With Manufacturer's Scan Tool

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

If malfunctions 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 different DTCs (See Diagnostic Trouble Code (DTC) table) and stores these until the contents of the DTC memory is erased. Testing and Inspection

Malfunctions which only occur sporadically will have the addendum "sporadic malfunction" on the print out. These malfunctions will be indicated on the display by the addendum "/SP." The cause of sporadic malfunctions 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 °C coolant temperature - switched off above 72 °C), it will be erased from the DTC memory.

The DTCs stored can be read-out with the scan tools VAG 1551 or 1552 or the tester VAS 5051. Reading Diagnostic Trouble Codes

The DTC memory must be erased after the malfunctions have been eliminated and the readiness code must be generated again. Monitors, Trips, Drive Cycles and Readiness Codes


If the DTC memory has been erased, the Motronic Engine Control Module (ECM) -J220- looses all the learned values for oxygen sensor control, idle speed and charge pressure. Therefore considerable driving characteristic problems may occur depending on vehicle mileage.

All values learned by the Motronic Engine Control Module (ECM) -J220- will be erased when the Motronic Engine Control Module (ECM) -J220- connector is disconnected or the battery is disconnected. However the contents of the DTC memory are retained. When the engine is subsequently started the idle could be rough for a brief period. In this case leave the engine running for a few minutes at idle speed or perform a longer test drive, until the learning process is completed. Procedure after voltage supply open circuit.
ECM Voltage Supply Open Circuit, Follow-up Procedure


NOTE: General information for On Board Diagnostic (OBD) can be found in the instruction manuals for the VAG 1551 or 1552 scan tools or the VAS 5051 scan tool.