Code
B2400
Generic
B — Body
Body Control Module (BCM) Power Supply Fault
Views:
UK: 22
EN: 30
RU: 26
AI status
Completed
Completed
100%
Causes
- Low or discharged battery
- Blown fuse or fusible link feeding the BCM
- Faulty ignition/accessory relay or wiring
- Corroded/damaged BCM power or ground connections
- Short/open in wiring harness to BCM power pin
- Intermittent supply due to connector contamination or water intrusion
Symptoms
- Illumination or flicker of interior/exterior lights
- Intermittent or total loss of body functions (door locks, wipers, windows, interior lights)
- Multiple body module communication errors on scan tool
- Instrument cluster warnings or inoperative displays
- Accessories operate only intermittently or not at all
- Vehicle may fail to unlock/lock or show odd behavior after key on
What to check
- Check battery state-of-charge and terminal condition (clean/tight).
- Inspect BCM area and connectors for corrosion, water intrusion, bent pins, or physical damage.
- Check all fuses and fusible links related to body/control modules and accessory circuits.
- Verify ignition/key switch and accessory relays that supply BCM power.
- Scan vehicle for additional U- or B-codes indicating communication faults.
- Measure voltage at BCM power feed pin with key OFF and key ON; measure ground continuity between BCM ground and battery negative.
Signal parameters
- Battery supply to BCM: ~11–14.6 V (engine off/charging vary) at battery terminals and at BCM power pin with key ON.
- Ground: near 0 V; low resistance (
- Ignition-switched feed present when key ON; should be near battery voltage when active.
- CAN bus recessive level ~2.5 V on both CAN_H and CAN_L (verify against vehicle spec).
- Key wake/sleep signals meet manufacturer timing and voltage specs (refer to service manual).
Diagnostic algorithm
- Record freeze frame and all related codes; note operating conditions when fault occurred.
- Verify battery voltage and health. Charge or replace battery if low and retest.
- Visually inspect BCM, mounting, connector sealing and wiring for damage/corrosion/water intrusion. Repair any found issues.
- Check fuses/fusible links and relays feeding the BCM; replace any blown components. Verify relay operation and coil feed/ground.
- With a DVOM, measure voltage at the BCM power pin(s) with key OFF and key ON; compare to battery terminal voltage. Look for voltage drops.
- Measure resistance/continuity from BCM ground to battery negative. Clean and tighten ground connections as required.
- Backprobe power and ground while operating affected circuits or performing a wiggle test to detect intermittent faults.
- Verify communication bus presence (CAN/LIN) and proper levels with an oscilloscope or lab scope if available.
- If wiring and supplies are confirmed good and within specification, consider BCM internal fault. Verify software/calibration and update if available before replacing module.
- If BCM replacement is required, follow manufacturer procedures for programming/encoding and protect anti-theft/immobilizer systems. Clear codes and retest road/use cycle to confirm repair.
Likely causes
- Blown BCM fuse or fusible link
- Loose or high-resistance ground at BCM or chassis
- Ignition-switched feed open or intermittent (relay or wiring)
- Corroded or water-damaged BCM connector pins
- Battery voltage sag under load or poor battery connections
Fault status
Status
BCM power supply outside expected range — low/absent/intermittent supply, fuse/relay/wiring/ground issue or internal BCM fault. Verify supply and grounds before replacing module.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Workshop Manuals
Available brands with manuals
2
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6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)
Workshop ManualAudi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002
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Workshop ManualLAND ROVER 3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
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Code
B2400
LAND ROVER
B — Body
Failure in the head retention potentiometer with battery weak Failure in the tape player mechanism audio
Views:
UK: 15
EN: 25
RU: 18
AI status
Completed
Completed
100%
Causes
- Low or discharged battery
- Blown fuse or fusible link feeding the BCM
- Faulty ignition/accessory relay or wiring
- Corroded/damaged BCM power or ground connections
- Short/open in wiring harness to BCM power pin
- Intermittent supply due to connector contamination or water intrusion
Symptoms
- Illumination or flicker of interior/exterior lights
- Intermittent or total loss of body functions (door locks, wipers, windows, interior lights)
- Multiple body module communication errors on scan tool
- Instrument cluster warnings or inoperative displays
- Accessories operate only intermittently or not at all
- Vehicle may fail to unlock/lock or show odd behavior after key on
What to check
- Check battery state-of-charge and terminal condition (clean/tight).
- Inspect BCM area and connectors for corrosion, water intrusion, bent pins, or physical damage.
- Check all fuses and fusible links related to body/control modules and accessory circuits.
- Verify ignition/key switch and accessory relays that supply BCM power.
- Scan vehicle for additional U- or B-codes indicating communication faults.
- Measure voltage at BCM power feed pin with key OFF and key ON; measure ground continuity between BCM ground and battery negative.
Signal parameters
- Battery supply to BCM: ~11–14.6 V (engine off/charging vary) at battery terminals and at BCM power pin with key ON.
- Ground: near 0 V; low resistance (
- Ignition-switched feed present when key ON; should be near battery voltage when active.
- CAN bus recessive level ~2.5 V on both CAN_H and CAN_L (verify against vehicle spec).
- Key wake/sleep signals meet manufacturer timing and voltage specs (refer to service manual).
Diagnostic algorithm
- Record freeze frame and all related codes; note operating conditions when fault occurred.
- Verify battery voltage and health. Charge or replace battery if low and retest.
- Visually inspect BCM, mounting, connector sealing and wiring for damage/corrosion/water intrusion. Repair any found issues.
- Check fuses/fusible links and relays feeding the BCM; replace any blown components. Verify relay operation and coil feed/ground.
- With a DVOM, measure voltage at the BCM power pin(s) with key OFF and key ON; compare to battery terminal voltage. Look for voltage drops.
- Measure resistance/continuity from BCM ground to battery negative. Clean and tighten ground connections as required.
- Backprobe power and ground while operating affected circuits or performing a wiggle test to detect intermittent faults.
- Verify communication bus presence (CAN/LIN) and proper levels with an oscilloscope or lab scope if available.
- If wiring and supplies are confirmed good and within specification, consider BCM internal fault. Verify software/calibration and update if available before replacing module.
- If BCM replacement is required, follow manufacturer procedures for programming/encoding and protect anti-theft/immobilizer systems. Clear codes and retest road/use cycle to confirm repair.
Likely causes
- Blown BCM fuse or fusible link
- Loose or high-resistance ground at BCM or chassis
- Ignition-switched feed open or intermittent (relay or wiring)
- Corroded or water-damaged BCM connector pins
- Battery voltage sag under load or poor battery connections
Fault status
Status
BCM power supply outside expected range — low/absent/intermittent supply, fuse/relay/wiring/ground issue or internal BCM fault. Verify supply and grounds before replacing module.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Workshop Manuals
Repair manuals for LAND ROVER
3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
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Send to email
Code
B2400
MITSUBISHI
B — Body
KOS key registration fail
Views:
UK: 17
EN: 26
RU: 22
AI status
Completed
Completed
100%
Causes
- Low or discharged battery
- Blown fuse or fusible link feeding the BCM
- Faulty ignition/accessory relay or wiring
- Corroded/damaged BCM power or ground connections
- Short/open in wiring harness to BCM power pin
- Intermittent supply due to connector contamination or water intrusion
Symptoms
- Illumination or flicker of interior/exterior lights
- Intermittent or total loss of body functions (door locks, wipers, windows, interior lights)
- Multiple body module communication errors on scan tool
- Instrument cluster warnings or inoperative displays
- Accessories operate only intermittently or not at all
- Vehicle may fail to unlock/lock or show odd behavior after key on
What to check
- Check battery state-of-charge and terminal condition (clean/tight).
- Inspect BCM area and connectors for corrosion, water intrusion, bent pins, or physical damage.
- Check all fuses and fusible links related to body/control modules and accessory circuits.
- Verify ignition/key switch and accessory relays that supply BCM power.
- Scan vehicle for additional U- or B-codes indicating communication faults.
- Measure voltage at BCM power feed pin with key OFF and key ON; measure ground continuity between BCM ground and battery negative.
Signal parameters
- Battery supply to BCM: ~11–14.6 V (engine off/charging vary) at battery terminals and at BCM power pin with key ON.
- Ground: near 0 V; low resistance (
- Ignition-switched feed present when key ON; should be near battery voltage when active.
- CAN bus recessive level ~2.5 V on both CAN_H and CAN_L (verify against vehicle spec).
- Key wake/sleep signals meet manufacturer timing and voltage specs (refer to service manual).
Diagnostic algorithm
- Record freeze frame and all related codes; note operating conditions when fault occurred.
- Verify battery voltage and health. Charge or replace battery if low and retest.
- Visually inspect BCM, mounting, connector sealing and wiring for damage/corrosion/water intrusion. Repair any found issues.
- Check fuses/fusible links and relays feeding the BCM; replace any blown components. Verify relay operation and coil feed/ground.
- With a DVOM, measure voltage at the BCM power pin(s) with key OFF and key ON; compare to battery terminal voltage. Look for voltage drops.
- Measure resistance/continuity from BCM ground to battery negative. Clean and tighten ground connections as required.
- Backprobe power and ground while operating affected circuits or performing a wiggle test to detect intermittent faults.
- Verify communication bus presence (CAN/LIN) and proper levels with an oscilloscope or lab scope if available.
- If wiring and supplies are confirmed good and within specification, consider BCM internal fault. Verify software/calibration and update if available before replacing module.
- If BCM replacement is required, follow manufacturer procedures for programming/encoding and protect anti-theft/immobilizer systems. Clear codes and retest road/use cycle to confirm repair.
Likely causes
- Blown BCM fuse or fusible link
- Loose or high-resistance ground at BCM or chassis
- Ignition-switched feed open or intermittent (relay or wiring)
- Corroded or water-damaged BCM connector pins
- Battery voltage sag under load or poor battery connections
Fault status
Status
BCM power supply outside expected range — low/absent/intermittent supply, fuse/relay/wiring/ground issue or internal BCM fault. Verify supply and grounds before replacing module.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Your experience will help others
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Was this AI description helpful?
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👍 Like
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0
Send to email