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B142E — Occupant Classification System: Sensor Circuit Malfunction

Detailed page for trouble code B142E.

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Code

B142E

LAND ROVER B — Body

Occupant Classification System: Sensor Circuit Malfunction

Brand: LAND ROVER
Type: B — Body
Views: UK: 6 EN: 12 RU: 7
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Page language: EN

Causes

  • Faulty occupant classification (seat weight) sensor or sensor mat
  • Damaged, corroded, or disconnected seat wiring harness or connector
  • Poor ground or loss of reference/supply from SRS/airbag control module
  • Water/moisture ingress or contamination of the seat sensor assembly
  • Intermittent connector contact due to movement or damaged pins
  • Faulty restraint control module (airbag ECU) or internal module fault

Symptoms

  • SRS/airbag warning lamp illuminated on dash
  • Passenger airbag disable/enable indicator may report incorrect status
  • Diagnostic trouble code B142E stored in airbag/BCM/OCS module
  • Passenger occupant classification not recognized or changes intermittently
  • Possible inability to arm/disable passenger airbag

What to check

  • Read and record all SRS/OCS related codes and freeze-frame data with a compatible scan tool
  • Visually inspect passenger seat, underside, and connectors for damage, corrosion, or moisture
  • Check for presence of aftermarket seat covers or recent seat repairs
  • Confirm whether airbag lamp is steady or flashing (consult manufacturer service info)
  • Perform wiggle test on seat wiring and connectors while watching live data for changes

Signal parameters

  • Supply/reference: typically vehicle 12V for power and a 5V or reference circuit for sensor electronics (varies by design)
  • Signal type: resistance-based mat or sensor network; ECU expects stable resistance or a voltage signal proportional to load
  • Fault indications: open/OL (infinite resistance), short to ground (near 0Ω), short to battery (~12V), or fluctuating/erratic values
  • Expected behavior: signal changes smoothly with applied weight; no sudden jumps or noise

Diagnostic algorithm

  1. Use a manufacturer-capable scan tool to read/record DTCs and live data from the occupant classification/airbag module. Note any related codes.
  2. Verify the SRS system is safe to inspect (remove key, disable battery per factory procedure and wait required time to avoid airbag deployment). Follow all SRS safety precautions.
  3. Visually inspect passenger seat cushion, seatback, underside, and connectors for damage, water, corrosion, or loose pins. Remove trim as required for access.
  4. Check connector continuity: backprobe the seat sensor connector and measure supply, reference, and ground with connector mated and ignition on (follow wiring diagram). Compare to expected voltages. Look for open/short.
  5. With scan tool, monitor occupant classification sensor values while applying weight to the seat. Note any missing or erratic response.
  6. Perform resistance checks of sensor mat (if service manual specifies values). Look for open circuits or shorted elements. If resistance values are out of range or OL, suspect sensor mat failure.
  7. Wiggle harness and move seat through full travel while monitoring live data and watching for intermittent faults. Repair any broken wires or poor contacts.
  8. Inspect for moisture contamination; dry or replace sensor mat if evidence of water ingress.
  9. If wiring and connectors test good, consider replacement of the occupant classification sensor/mat or seat module per manufacturer procedure. Reprogram or reset the airbag/OCS module if required after replacement.
  10. After repairs, clear codes and perform functional tests with scan tool. Confirm SRS lamp extinguishes and OCS reports valid occupancy states across expected weight ranges.

Likely causes

  • Open or shorted sensor element inside the seat mat (most likely)
  • Corroded/loose connector at the seat or ECU
  • Moisture damage to sensor mat or cabling (common in wet vehicles)
  • Broken wire in seat harness due to seat adjustment movement
  • Faulty seat module or airbag control module (less common)

Fault status

⚠️ Status
B142E — Occupant Classification System sensor circuit malfunction. Passenger seat occupancy sensor circuit open/short/intermittent. SRS warning lamp illuminated; passenger airbag may be disabled.
🔴 Repair difficulty: Hard
⏱️ Diagnostic time: 1.0-3.0 hours

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