Simultaneous Replacement Of CAS Control Unit And Instrument Cluster
WARNING: This page is about a different car, the 2005 BMW 645Ci and 2004 BMW 645Ci. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Do not replace the CAS control unit and the instrument cluster at the same time.
Avoid simultaneous exchange of the CAS control unit and instrument cluster due to the risk of the current kilometer reading and all CBS data being irrevocably lost.
Follow the steps below if it is necessary to replace both control units at the same time (e.g. neither respond to the BMW diagnosis system):
- Replace the instrument cluster
- Encode the VIN in the instrument cluster
- Switch terminal 15 OFF, then ON. There may actually be a transfer of data between the CAS control unit and the instrument cluster.
- Replace the CAS control unit
- Encode the VIN in the CAS control unit
- Switch terminal 15 off then on again.
- The manipulation dot is cleared after the terminal 15 is switched back on. Communication between the instrument cluster and CAS control unit for redundant data storage is now ensured.