B12D6

Code

LAND ROVER B — Body

Quick door unlocking / actuator open

Brand: LAND ROVER

Type: B — Body

Views: UK: 18 EN: 35 RU: 20

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Failed or seized door lock actuator or latch mechanism
Damaged wiring or poor connector at door harness
Corroded or water-damaged connector or actuator
Short or open in actuator power/ground or position sensor circuit
Faulty Body Control Module (BCM) or Door Control Unit (DCU)
Software issue or intermittent module communication error

Symptoms

Door unlocks quickly, erratically, or unlocks without command
Central locking operates intermittently or only one door affected
Key fob or interior unlock switch has no consistent effect
Interior light may behave unexpectedly when unlocking
Possible battery drain if actuator runs continuously
Warning or message on dash for door open/ajar

What to check

Read stored DTCs and any related body or communication codes with a capable scan tool
Reproduce the symptom and note which door is affected and conditions
Visually inspect door wiring at hinge/boot for chafe, breaks, or pinched wires
Inspect actuator connector for corrosion, bent pins, or water ingress
Check relevant fuses and relays for the central locking/BCM circuits
Check for software updates or Technical Service Bulletins affecting door modules

Signal parameters

Actuator control: switched battery voltage when commanded (0 V idle, ~12 V when powered)
Expected actuator motor current: typically under 5 A momentary (varies by model)
Position/limit switch: binary open/closed signal to BCM (0 V / battery voltage)
Resistance of actuator windings: low ohms when measured cold (manufacturer-specific)
CAN/lin messages: door module should report status changes to BCM (verify with scan tool)

Diagnostic algorithm

Retrieve code(s) and freeze/frame data with a diagnostic scanner; record which door reported the fault.
Attempt to reproduce: operate locks via key fob, interior switch, and scan tool command while observing behavior.
Visually inspect door harness at the hinge/boot and connector at the actuator for damage, corrosion, or water.
With door closed and ignition on, back-probe actuator power and ground while commanding lock/unlock; verify voltage is present and switching as commanded.
Measure actuator current draw during operation. Excessive current suggests mechanical binding; no current suggests open circuit.
Check continuity and resistance of the actuator motor/position switch wiring to the BCM; repair any breaks or high-resistance connections.
If wiring and power/ground are good but actuator behaves incorrectly, remove door trim and bench-test or swap the actuator with a known-good unit where possible.
Inspect and test the door latch/position sensor; replace latch or sensor if it reports incorrect open/closed states.
If actuator and wiring test OK, inspect BCM/door module inputs and outputs via scan tool; consider reflash or replacement if module is faulty.
After repairs, clear codes and verify repair by repeating function tests and confirming no return of DTC.

Likely causes

Door lock actuator motor or internal switch failure
Wiring harness damage at the door hinge/boot area
Corrosion at actuator connector or terminals
Intermittent ground connection at door or BCM
Faulty door latch position sensor

Fault status

⚠️ Status

Quick door unlocking / actuator open detected. The door actuator or latch position sensor reported an unexpected open/actuated condition or the BCM detected an anomaly on the lock actuator circuit.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

Repair manuals

Manual library for LAND ROVER

413

Browse 413 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