Ignition System: Description and Operation

Ignition, Servicing

General notes on ignition system
- This section deals specifically with ignition related components. The other components of the injection and ignition system.
- For the electric components to work properly, a voltage of at least 11.5 V is required.
- The battery must only be disconnected and connected with the ignition switched off, since the Engine Control Module (ECM) can otherwise be damaged.
- The Engine Control Module (ECM) is equipped with an On Board Diagnostic (OBD)
- Components marked with * are tested via On Board Diagnostic (OBD), Diagnostic mode 3: Check DTC memory.
- It is possible that the control module will recognize a malfunction and store a DTC during some tests. Therefore the following work steps must be performed in the mentioned sequence after ending all tests and repairs.

- Check DTC memory, Diagnostic mode 3: Check DTC Memory. Diagnostic Mode 3: Check DTC Memory
- Erase DTC memory, Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- For completion, generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

Parts of ignition, removing and installing:
- Vehicles with engine code AEG.
- Vehicles with engine code AVH, AZG, BDC.

Safety precautions.
Test data, spark plugs.