Ignition System: Description and Operation

Ignition System, Checking

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.