Functional check:

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Switch ignition on: the EPC warning lamp must light-up.

If the EPC warning lamp does not light-up with ignition switched on:

Check combi-instrument and EPC warning lamp as follows: → 01 ON BOARD DIAGNOSTIC (OBD)

If the EPC warning lamp lights-up with ignition switched on, continue check as follows:

Start engine and run at idling speed: EPC warning lamp must go out after a few seconds.

If the EPC warning lamp does not go out:

Check DTC Memory, if necessary, repair any malfunctions and then Erase DTC Memory → DTC memory (functions 02 and 05), checking and erasing , interrogating and erasing DTC memory.
Read readiness code → Readiness code, reading . If the DTC memory has been erased, the readiness code must be generated again

Engine code AWW, → Readiness code for engine code AWW, generating

Engine code AWP, → Readiness code for engine code AWP, generating