BMW CAS faults are normally either related to the battery, Keys, an ECU change or the actual CAS unit failing. Using BMW ISTA + we are able to diagnose issues with the CAS and any other control unit fitted to a BMW vehicle. The first stop when you have a CAS related issue is to perform a CAS hard reset this can ONLY be performed using ISTA or at a BMW dealer. Performing a HARD RESET will keep the ISN details and can solve many issues. If issues persist after this we are able to update the cas unit to the latest version (this is advised anyway) outdated control units can cause many issues.
CAS Sync when either changing the battery or changing the DDE / Engine ECU, After changing the battery you can throw the CAS and DDE ISN code out of SYNC. To re sync the CAS is a very simple procedure and can be done either at our workshop in Saxmundham, Suffolk or in most cases we are able to provide a mobile service in suffolk, essex and norfolk.