U1021 — BMW — Lost Communication With A/C Clutch

U1021 (BMW): Lost Communication With A/C Clutch — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

The system is failing to receive status data from the air conditioning clutch via the communication network. Manufacturer-specific definition; confirm applicability in the service information for the exact vehicle.

Affected system: Network