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Home >> Volvo >> 2004 >> S40 LSE >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Dynamic Stability Assist (DSA) & Electronic Control Module (ECM) Diagnostic Trouble Codes (644 Body) >> DSA-223: Engine Control Module (ECM) Initialization. Faulty Signal (B4204T2 CVVT; 2000) >> Faulty signal >> Replacing engine control module (ECM) >> Replacing engine control module (ECM)
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Replacing engine control module (ECM)

Fig 1: Identifying Bracket And Security Screws
GLL114152Courtesy of VOLVO CARS OF NORTH AMERICA.

Before replacing the engine control module with a new one, the Verlog code of the old module has to be erased. The code is erased through VIDA which is used for communication with the immobilizer system through VCT 2000. If the code is not erased, the control module cannot be checked if it is returned due to a warranty claim, or if it is to be moved to another car. This is caused by the module having learned the Verlog code generated by the immobilizer system of the car in which the module has been placed. When that has been done, the engine control module can only work together with that specific immobilizer system, as long as the Verlog code in the module is not erased.

NOTE:

The Verlog-code can only be erased using the particular immobilizer- control module whose Verlog-code the engine control module (ECM) has learned.

Erase the Verlog code in the engine control module. The PIN code is supplied by Volvo's central vehicle register. PIN codes are ordered in the same way as mechanical key codes.

NOTE:

Keep the ignition switched off after erasure until the engine control module (ECM) has been removed from the car. Otherwise the engine control module (ECM) will relearn the Verlog code.