B10C2

Code

LAND ROVER B — Body

switch left rear unlock

Brand: LAND ROVER

Type: B — Body

Views: UK: 19 EN: 34 RU: 18

AI status

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Page language: EN

Causes

Failed left rear door unlock switch (mechanical or electrical)
Open or shorted wiring between switch and BCM or door module
Corroded or loose connector at switch or door module
Failed left rear door lock actuator or latch wiring
Faulty Body Control Module or door control module
Water ingress or physical damage in door harness

Symptoms

Left rear door does not unlock from its interior switch
Intermittent or inconsistent unlock operation for left rear door
Left rear door may unlock from remote/key fob but not from switch (or vice versa)
Door lock warning or message on dash (depending on vehicle)
Other door unlock switches operate normally

What to check

Use a diagnostic scan tool to read the code, freeze frame and live data for the door switch input and BCM outputs
Visually inspect left rear door switch, surrounding trim and connector for corrosion, water intrusion or damage
Check fuses and relays supplying the door lock/switch circuit
Operate the left rear unlock switch while monitoring voltage and continuity with a multimeter
Wiggle test wiring with switch actuated to reproduce intermittent faults
Inspect and test left rear door lock actuator for correct operation and current draw

Signal parameters

Key On (accessory): switch supply voltage ≈ battery voltage (approx. 12 V)
Switch actuation: output should change state (either pulled to ground or supplied with battery voltage depending on design)
Closed switch terminal resistance: typically near 0–5 ohms (very low); open circuit: very high (kΩ to MΩ)
Short to battery: near 0 V across fuse or abnormal battery voltage on signal when switch not pressed
Short to ground: signal held at ~0 V when it should be open/high
CAN/Module: unlock command present from BCM or door module when unlock requested

Diagnostic algorithm

Retrieve and record DTC and any freeze frame with a scan tool. Note whether code is current or historic.
Visually inspect left rear door trim, switch and connector for damage, corrosion, moisture, or pushed-out pins. Repair as needed.
Check relevant fuses/relays. Replace any blown fuses and retest.
With ignition ON, probe the switch connector: verify supply voltage present and measure switch output while pressing/unpressing the switch. Compare to expected behavior.
Perform continuity test between switch output terminal and BCM/door module input pin with connectors disconnected. Check for opens or high resistance.
Wiggle the harness and operate the switch to try to reproduce the fault. Inspect areas where harness passes through door hinge for chafing.
If the switch wiring and connector are good, command unlock from scan tool and measure actuator response/current draw to rule out actuator-related faults.
If wiring, switch and actuator test good, check BCM/door module for proper inputs and outputs using a scope or scan tool; consider reflashing or replacement only after wiring and switch verified.
After repair or component replacement, clear DTC and perform functional tests (multiple cycles, road test if required) to confirm fault is resolved.

Likely causes

Switch contact wear or contamination preventing consistent contact
Connector corrosion at the door harness or switch
Chafed wiring causing intermittent short to ground or battery
Damaged door lock actuator drawing excess current and causing circuit fault
Poor grounding at door/chassis causing false/unreadable switch signal

Fault status

⚠️ Status

Body Control Module detected a fault in the left rear door unlock switch circuit — signal out of range, open circuit, short to ground/battery, or implausible input compared to expected behavior.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours

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Manual library for LAND ROVER

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Browse 413 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

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