Many people who own a pre 03/98 build date non M Z3's find it hard to scan any modules other than the engine computer (DME). This is because before 03/98, the Z3 has a mix of OBD1/ADS and OBD2 modules. 03/98 and later, the non M Z3's have all OBD2 modules. Seem that the USA S52 Z3M's had ADS...
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