Malfunction recognition

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If malfunctions occur at the exhaust relevant systems or components, they are stored in DTC memory with a description of the malfunction type.

The stored malfunctions can be checked with a standard diagnostic tester. See MODE 3: CHECK DTC MEMORY .

The Engine Control Module (ECM) differentiates between different DTCs after evaluating the information. See DIAGNOSTIC TROUBLE CODE (DTC) TABLES: .

If the ECM recognizes malfunctions that lead to a worsening of emissions values, it indicates them by lighting the Malfunction Indicator Lamp (MIL) -K83- in the instrument cluster. See MALFUNCTION LAMP FOR ON BOARD DIAGNOSTIC (OBD)/MALFUNCTION INDICATOR LAMP (MIL) -K83- IN INSTRUMENT CLUSTER .

E-Gas -relevant malfunctions are also indicated by the Electronic Power Control (EPC) Warning Lamp -K132- ("EPC warning lamp") in the instrument cluster. See ELECTRONIC POWER CONTROL (EPC) WARNING LAMP -K132- IN INSTRUMENT CLUSTER .

When disconnecting harness connectors from Engine Control Module (ECM) or when disconnecting battery, all adaptation values in the control module are erased. DTC memory content will remain intact however. After re - connecting harness connectors or battery, the following work steps must be performed in the mentioned sequence:

- Check DTC memory. See MODE 3: CHECK DTC MEMORY .
- If necessary, erase DTC memory. See MODE 4: RESET/ERASE DIAGNOSTIC DATA .
- If DTC memory was erased, generate readiness code. See READINESS CODE, GENERATING .

End diagnosis and switch ignition off.