From 2/89 to 9/91 Production
The E32/E34 instrument cluster and coding plug were redesigned in 2/89. As a result of this redesign the coding plug became an external component and plugged directly into the back of the instrument cluster, no longer part of the X16 connector.
Even though the plug can be removed without disconnecting the harness, all power must be disconnected from the cluster prior to removal, to prevent data loss from the coding plug.