On-Board Diagnostic

On Board Diagnostic

The Engine Control Module (Motronic Engine Control Module (ECM) -J220- is equipped with DTC memory.

If malfunctions occur in emissions-related systems or components, they are stored in DTC memory with a description of the malfunction type.

The Engine Control Module (ECM) differentiates between different DTCs after evaluating the information, Testing and Inspection

Stored malfunctions can be retrieved using a commercially available tester. Diagnostic Mode 03 - Read DTC Memory

When harness connectors are disconnected from the Engine Control Module (ECM) or the battery is disconnected, all adaptation values in the control module are erased. However, DTC memory content will remain intact. If the engine is started after this, the idle may be rough for a short period. In this case, the readiness code must be generated again. Generate Readiness Code

The following work steps must be performed in the described sequence after the malfunction(s) have been repaired:

1. Check DTC memory. Diagnostic Mode 03 - Read DTC Memory
2. Erase DTC memory. Diagnostic Mode 04 - Erase DTC Memory
3. Then generate readiness code. Generate Readiness Code

On Board Diagnostic, Technical Data
Selectable diagnostic modes under address word 33 - OBD. Selectable Diagnostic Modes Under Address Word 33, OBD