BMU5 Loss of ECU ID data
â–¶ How to fix
Replace the BMU(E81) unit since ECU complete number cannot be recovered/rewritten by SDP3.
What you'll see
No driver-visible symptom recorded.
System reaction
Limited support in SDP3 (since the ECU complete number cannot be identified)
Diagnostic depth
Detection
File containing ECU identification data is found to be inconsistent or missing at start of ECU. The ECU-ID data could not be read from the persistent memory.
Possible cause
System supply voltage (U30) was cut off while the ECU was writing to the file containing the ECU identification data.