B1B21

Code

LAND ROVER B — Body

Key of identifier 19

Brand: LAND ROVER

Type: B — Body

Views: UK: 22 EN: 23 RU: 25

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Key transponder or key fob not programmed for this vehicle
Corrupted or erased key identifier data in immobilizer/BCM
Damaged key transponder or internal key electronics
Weak or dead key fob battery
Faulty key antenna/coil or poor antenna grounding
Intermittent or failed communication on CAN or LIN between immobilizer, BCM and instrument cluster

Symptoms

Engine cranks but will not start, or no crank depending on immobilizer state
Security/immobilizer warning lamp illuminated or flashing
Key not recognised message on dash or infotainment
Remote locking/unlocking or push-button start inconsistent for that key
Other keys work normally (if present)

What to check

Scan all modules for related codes and note freeze frame/occurrence data
Try a known-good or spare programmed key to compare behaviour
Check and replace key fob battery if low
Inspect physical key/fob for damage, moisture or corrosion
Verify antenna/reader wiring and connectors at ignition or reader unit
Check CAN/LIN communication and power/ground to immobilizer/BCM

Signal parameters

Transponder ID (immobilizer key serial number)
Key presence/recognition flag from immobilizer (boolean)
Antenna coil voltage/amplitude during key read
Key fob RF rolling code / remote ID
CAN bus messages between immobilizer, BCM and engine ECU (e.g., key auth status)
Module power (VBATT) and ground integrity at immobilizer/BCM

Diagnostic algorithm

Retrieve full DTC list from all modules. Note any communication faults or related B/U or U-codes.
Confirm symptom with customer: which key(s) fail, when it occurs, history of battery disconnection or key replacements.
Test a known-good programmed key. If it works, suspect the reported key (identifier 19) is unprogrammed or faulty.
Replace or fit a fresh battery in the suspect key; retest recognition and remote functions.
Inspect key/fob for physical damage; if suspected internal failure, test or replace the key/fob.
Using manufacturer diagnostic tools, read the immobilizer/BCM key list and check for entry relating to identifier 19. Attempt to reprogram or delete/re-add the key per factory procedure.
Check antenna/reader function: measure coil voltage when key present and inspect wiring/connectors for corrosion or damage.
Verify CAN/LIN communication and module power/ground. Repair wiring or connectors as required.
If key and wiring are good but identifier still not recognised, follow manufacturer procedure to reflash or replace immobilizer/BCM.
Clear DTCs and retest multiple start/lock cycles and both keys where available to confirm resolution.

Likely causes

Unprogrammed replacement key (most common)
Failed transponder inside the key (water damage or impact)
Antenna coil around ignition/near reader is faulty
Immobilizer module lost stored keys after battery disconnect or software update

Fault status

⚠️ Status

Immobilizer/key ID error — Key identifier 19 not recognised or invalid. Vehicle security may prevent engine start or remote functions until key is validated or repaired.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1-3 hours

Similar codes

Repair manuals

Manual library for LAND ROVER

332

Browse 332 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

Your experience will help others

+100 karma for a short comment :)

Was this AI description helpful?

Your feedback helps improve AI descriptions.

👍 Like 0 👎 Dislike 0

Send to email