Code
B1071
HUMMER
B — Body
Driver Door Unlock Request Switch Circuit Fault
Views:
UK: 10
EN: 18
RU: 16
AI status
Completed
Completed
100%
Causes
- Faulty driver door unlock-request switch
- Open or shorted wiring between switch and BCM
- Corroded or loose connector pins at switch or BCM
- Water intrusion in door harness or switch assembly
- Poor or missing ground for the switch circuit
- Blown fuse or faulty body control module (less common)
Symptoms
- Driver door does not unlock when using the interior unlock switch
- Switch may work intermittently or require holding to operate
- DTC B1071 stored; possible related DTCs
- Other doors may still unlock (key fob or passenger switch may work)
- No illumination of the switch or unexpected lamp behavior (if applicable)
What to check
- Read and record freeze-frame and related codes with a scan tool; note conditions when fault set
- Inspect driver door switch and surrounding trim for moisture or damage
- Visually inspect harness through door hinge/boot for chafing or damage
- Check connectors for corrosion, bent pins, or poor seating at switch and BCM
- Verify relevant fuses and power/ground circuits
- Backprobe the switch connector and monitor signal while operating the switch
Signal parameters
- Normal: switch presents defined change to BCM input when pressed (either pulls input to ground or to vehicle battery voltage depending on design)
- Expected voltage with switch idle: depends on system (often ~12 V through pull-up or ~open/high impedance to module input)
- Expected voltage when active: typically ~0 V (pulled to ground) or ~12 V depending on manufacturer wiring
- Continuity: near 0 Ω across switch when closed; open (infinite) when open
- Resistance to chassis ground: should be consistent and show no short to power when switch is open
Diagnostic algorithm
- Using a scan tool, confirm B1071 is active or was recently stored. Note freeze-frame data and any related codes (lock/unlock switch codes, communication codes).
- Perform a visual inspection of the driver door switch, harness, connectors, and door boot for corrosion, pin damage, water ingress, or chafed wires.
- Confirm fuses and power/ground circuits servicing the door switches are present and good.
- Backprobe the switch connector with the ignition on and monitor the signal while operating the switch. Compare observed voltage behavior to expected: switch open vs pressed.
- If no valid signal change, disconnect the switch and measure continuity across switch terminals while actuating. Replace switch if contacts do not change state correctly.
- If the switch tests good, test continuity from the switch connector to the BCM input pin with connectors disconnected (check for opens). Repair any open circuits.
- Check for shorts to battery or chassis by measuring resistance from the signal wire to 12 V and to ground with the circuit disconnected; repair as required.
- With wiring proven good and switch replaced if necessary, clear codes and retest operation over several cycles and drive conditions to ensure fault does not return.
- Only consider BCM replacement after completing wiring and switch verification; if BCM suspected, check for software updates and confirm module faults with manufacturer procedures before replacement.
Likely causes
- Switch contacts worn or contaminated from use or moisture
- Pin corrosion or bent pins at the door harness connector
- Wire chafed where harness passes through door hinge/boot causing intermittent open/short
- Connector not fully seated after door panel service
- Short to battery or chassis ground at a damaged section of cable
Fault status
Status
Driver Door Unlock Request Switch Circuit Fault — open/short/intermittent signal to BCM
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
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
Code
B1071
LAND ROVER
B — Body
Arc piston sensor voltage
Views:
UK: 8
EN: 15
RU: 12
AI status
Completed
Completed
100%
Causes
- Faulty driver door unlock-request switch
- Open or shorted wiring between switch and BCM
- Corroded or loose connector pins at switch or BCM
- Water intrusion in door harness or switch assembly
- Poor or missing ground for the switch circuit
- Blown fuse or faulty body control module (less common)
Symptoms
- Driver door does not unlock when using the interior unlock switch
- Switch may work intermittently or require holding to operate
- DTC B1071 stored; possible related DTCs
- Other doors may still unlock (key fob or passenger switch may work)
- No illumination of the switch or unexpected lamp behavior (if applicable)
What to check
- Read and record freeze-frame and related codes with a scan tool; note conditions when fault set
- Inspect driver door switch and surrounding trim for moisture or damage
- Visually inspect harness through door hinge/boot for chafing or damage
- Check connectors for corrosion, bent pins, or poor seating at switch and BCM
- Verify relevant fuses and power/ground circuits
- Backprobe the switch connector and monitor signal while operating the switch
Signal parameters
- Normal: switch presents defined change to BCM input when pressed (either pulls input to ground or to vehicle battery voltage depending on design)
- Expected voltage with switch idle: depends on system (often ~12 V through pull-up or ~open/high impedance to module input)
- Expected voltage when active: typically ~0 V (pulled to ground) or ~12 V depending on manufacturer wiring
- Continuity: near 0 Ω across switch when closed; open (infinite) when open
- Resistance to chassis ground: should be consistent and show no short to power when switch is open
Diagnostic algorithm
- Using a scan tool, confirm B1071 is active or was recently stored. Note freeze-frame data and any related codes (lock/unlock switch codes, communication codes).
- Perform a visual inspection of the driver door switch, harness, connectors, and door boot for corrosion, pin damage, water ingress, or chafed wires.
- Confirm fuses and power/ground circuits servicing the door switches are present and good.
- Backprobe the switch connector with the ignition on and monitor the signal while operating the switch. Compare observed voltage behavior to expected: switch open vs pressed.
- If no valid signal change, disconnect the switch and measure continuity across switch terminals while actuating. Replace switch if contacts do not change state correctly.
- If the switch tests good, test continuity from the switch connector to the BCM input pin with connectors disconnected (check for opens). Repair any open circuits.
- Check for shorts to battery or chassis by measuring resistance from the signal wire to 12 V and to ground with the circuit disconnected; repair as required.
- With wiring proven good and switch replaced if necessary, clear codes and retest operation over several cycles and drive conditions to ensure fault does not return.
- Only consider BCM replacement after completing wiring and switch verification; if BCM suspected, check for software updates and confirm module faults with manufacturer procedures before replacement.
Likely causes
- Switch contacts worn or contaminated from use or moisture
- Pin corrosion or bent pins at the door harness connector
- Wire chafed where harness passes through door hinge/boot causing intermittent open/short
- Connector not fully seated after door panel service
- Short to battery or chassis ground at a damaged section of cable
Fault status
Status
Driver Door Unlock Request Switch Circuit Fault — open/short/intermittent signal to BCM
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Workshop Manuals
Repair manuals for LAND ROVER
3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop Manual199,00 UAH
Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop Manual199,00 UAH
Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop Manual199,00 UAH
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
Code
B1071
MITSUBISHI
B — Body
R.air outlet DMPR.potentio.high
Views:
UK: 9
EN: 16
RU: 13
AI status
Completed
Completed
100%
Causes
- Faulty driver door unlock-request switch
- Open or shorted wiring between switch and BCM
- Corroded or loose connector pins at switch or BCM
- Water intrusion in door harness or switch assembly
- Poor or missing ground for the switch circuit
- Blown fuse or faulty body control module (less common)
Symptoms
- Driver door does not unlock when using the interior unlock switch
- Switch may work intermittently or require holding to operate
- DTC B1071 stored; possible related DTCs
- Other doors may still unlock (key fob or passenger switch may work)
- No illumination of the switch or unexpected lamp behavior (if applicable)
What to check
- Read and record freeze-frame and related codes with a scan tool; note conditions when fault set
- Inspect driver door switch and surrounding trim for moisture or damage
- Visually inspect harness through door hinge/boot for chafing or damage
- Check connectors for corrosion, bent pins, or poor seating at switch and BCM
- Verify relevant fuses and power/ground circuits
- Backprobe the switch connector and monitor signal while operating the switch
Signal parameters
- Normal: switch presents defined change to BCM input when pressed (either pulls input to ground or to vehicle battery voltage depending on design)
- Expected voltage with switch idle: depends on system (often ~12 V through pull-up or ~open/high impedance to module input)
- Expected voltage when active: typically ~0 V (pulled to ground) or ~12 V depending on manufacturer wiring
- Continuity: near 0 Ω across switch when closed; open (infinite) when open
- Resistance to chassis ground: should be consistent and show no short to power when switch is open
Diagnostic algorithm
- Using a scan tool, confirm B1071 is active or was recently stored. Note freeze-frame data and any related codes (lock/unlock switch codes, communication codes).
- Perform a visual inspection of the driver door switch, harness, connectors, and door boot for corrosion, pin damage, water ingress, or chafed wires.
- Confirm fuses and power/ground circuits servicing the door switches are present and good.
- Backprobe the switch connector with the ignition on and monitor the signal while operating the switch. Compare observed voltage behavior to expected: switch open vs pressed.
- If no valid signal change, disconnect the switch and measure continuity across switch terminals while actuating. Replace switch if contacts do not change state correctly.
- If the switch tests good, test continuity from the switch connector to the BCM input pin with connectors disconnected (check for opens). Repair any open circuits.
- Check for shorts to battery or chassis by measuring resistance from the signal wire to 12 V and to ground with the circuit disconnected; repair as required.
- With wiring proven good and switch replaced if necessary, clear codes and retest operation over several cycles and drive conditions to ensure fault does not return.
- Only consider BCM replacement after completing wiring and switch verification; if BCM suspected, check for software updates and confirm module faults with manufacturer procedures before replacement.
Likely causes
- Switch contacts worn or contaminated from use or moisture
- Pin corrosion or bent pins at the door harness connector
- Wire chafed where harness passes through door hinge/boot causing intermittent open/short
- Connector not fully seated after door panel service
- Short to battery or chassis ground at a damaged section of cable
Fault status
Status
Driver Door Unlock Request Switch Circuit Fault — open/short/intermittent signal to BCM
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
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