General Notes on Ignition System

General Notes On Ignition System

- Always switch off the ignition before connecting or disconnecting the battery, otherwise the Engine Control Module (ECM) may be damaged.
- A voltage of at least 12.7 V is necessary for satisfactory functioning of the electrical components.
- In the case of some tests, a malfunction may be recognized and stored by the control module. At the end of all tests and repairs, therefore, the DTC memory should be checked and, if necessary, erased.
- If the engine starts briefly and then stops after DTC search, repair or tests on components, this may be because the Immobilizer is blocking the Engine Control Module (ECM). The DTC memory must then be checked and, if necessary, adaptation carried out on the control module.

CAUTION:
- Measures to be taken prior to disconnecting the battery:
- Always switch off the ignition before connecting or disconnecting the battery, otherwise the engine control unit may be damaged.



General Notes On Ignition System

Check the Technical Bulletins for information that may supersede any information included.

NOTE:
- All manufacturers special tools as well as common tools may contain a manufacturer specific part number. These tools may be substituted with an equivalent aftermarket tool or are available for purchase through Audi.
- Manufacturers special tools as well as common tools that contain a manufacturer specific part number may be referenced in the test procedure illustrations showing the tool use or installation. If the manufacturer specific tool is not being used, an equivalent aftermarket tool may be installed in the same manner as the manufacturers special tool.
- The manufacturers test box Test Box 105 Pin VAG1598/31 is available for purchase or rental.