In some 2021 models, this is a known software glitch where the module expects a signal it isn't receiving. A dealer-level software update can often clear the persistent fault.
: Clear the DTC and determine if it returns immediately (hard fault) or after driving (intermittent fault). Visual Inspection land rover b1d9f11 2021
: In some 2021 models, the TCU may incorrectly read ground transients, which can sometimes be resolved with a software update rather than physical repair. Recommended Next Steps In some 2021 models, this is a known
2021 Land Rover Fault Code: B1D9F11 Code Structure: DTC (Diagnostic Trouble Code) – Body (B) / Proprietary (1) / DTC Descriptor (D9) In some 2021 models