Guys - I mentioned the Speed Sensor because the OP mentioned inoperative Speedometer, cruise and such. I know someone who had same symptoms on an E38 and it turned out to be frayed wires on that particular Speed Sensor. Usually on these era BMWs, when things like the Speedometer and Cruise control stop working it's because the Speed Sensor is no longer sending a signal.

With the additional information about the intermittent SES and TFSP warnings, I would suggest either load testing the battery or checking the alternator / battery voltage by opening up the cluster and doing a voltage check.

These cars do not take kindly to weak or faulty batteries.

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