Code
B2650
Generic
B — Body
Occupant Classification System (OCS) Sensor Circuit Malfunction
Views:
UK: 9
EN: 10
RU: 9
AI status
Completed
Completed
100%
Causes
- Damaged or disconnected connector at the occupant sensor/seat module
- Broken, pinched, chafed, or shorted wiring in the seat harness (common where harness passes under seat)
- Faulty occupant classification sensor mat or sensor module
- Corrosion, water intrusion, or contamination in seat area or connectors
- Poor or missing ground or reference voltage to the sensor
- Faulty airbag/occupant classification control module or related ECU
Symptoms
- SRS / airbag warning lamp ON
- Passenger airbag status indicator (ON/OFF) incorrect or unavailable
- Passenger airbag disabled or not deploying per normal logic
- DTC B2650 stored in airbag/OCS control module; may be intermittent
- Possible inability to complete vehicle self-test or to power cycle without code returning
What to check
- Read and record stored codes, freeze frame and lamp status with a capable scan tool
- Visually inspect passenger seat, underside, and all connectors for damage, corrosion, contamination or water
- Check for recent work on seat (reupholstery, replacement, sensors disturbed)
- Perform a wiggle test of seat harness/connectors while watching live data for the OCS sensor
- Verify battery voltage and perform recommended SRS power-down procedure before working on airbags
- Inspect grounds and power/reference supply to the OCS sensor/module
Signal parameters
- Reference voltage commonly 5 V (check OEM spec); sensor signal typically varies with occupancy
- Power supply to sensor may be switched 12 V or fused feed—verify per vehicle data
- Signal line expected to change value with occupant presence (voltage or resistance change)
- Ground continuity: near 0 ohms to chassis ground
- Communication may be on LIN/CAN or a dedicated analog signal depending on vehicle; compare live-data values to OEM expected ranges
Diagnostic algorithm
- Use a scan tool to read SRS/OCS live data and confirm B2650 is current or historic; record freeze-frame data.
- Disable battery power and wait required time per manufacturer before accessing airbag/seat components.
- Visually inspect the seat cushion area, connectors under the seat, and the occupant sensor mat for obvious damage, water, or contaminants.
- Reconnect and reseat all related connectors; clean contacts if corroded. Ensure connector latches are fully engaged.
- With battery reconnected and scan tool monitoring OCS data, perform a wiggle test of the seat wiring and connectors to look for intermittent changes or return of the code.
- Measure reference voltage, signal voltage and ground at the sensor connector using a DMM and compare to manufacturer specifications.
- Check continuity between the sensor connector and the airbag/OCS control module. Repair any open/shorted wiring found (insulate, replace harness sections, repair terminals).
- If wiring and connectors test normal, measure sensor mat resistance or sensor output per service manual; replace the occupant classification sensor/mat if out of spec.
- If sensor and wiring are good, verify module operation and communications; consider replacement or reprogramming of the OCS/airbag control module only after confirming wiring/sensor faults are not present.
- Clear codes, cycle ignition and retest. Confirm SRS lamp extinguishes and passenger airbag status behaves correctly. Road/test as required.
Likely causes
- Loose or corroded connector under the passenger seat
- Damaged wiring caused by seat movement or abrasion
- Failed occupant classification mat/sensor module
- Intermittent connector contact from contamination or moisture
Fault status
Status
Occupant Classification System sensor circuit malfunction detected. Passenger presence sensor signal out of expected range — inspect seat sensor, wiring, and connectors.
Repair difficulty: Medium
Diagnostic time: 1.0 - 2.5 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
B2650
LAND ROVER
B — Body
Antenna circuit - short circuit 1
Views:
UK: 17
EN: 26
RU: 16
AI status
Completed
Completed
100%
Causes
- Damaged or disconnected connector at the occupant sensor/seat module
- Broken, pinched, chafed, or shorted wiring in the seat harness (common where harness passes under seat)
- Faulty occupant classification sensor mat or sensor module
- Corrosion, water intrusion, or contamination in seat area or connectors
- Poor or missing ground or reference voltage to the sensor
- Faulty airbag/occupant classification control module or related ECU
Symptoms
- SRS / airbag warning lamp ON
- Passenger airbag status indicator (ON/OFF) incorrect or unavailable
- Passenger airbag disabled or not deploying per normal logic
- DTC B2650 stored in airbag/OCS control module; may be intermittent
- Possible inability to complete vehicle self-test or to power cycle without code returning
What to check
- Read and record stored codes, freeze frame and lamp status with a capable scan tool
- Visually inspect passenger seat, underside, and all connectors for damage, corrosion, contamination or water
- Check for recent work on seat (reupholstery, replacement, sensors disturbed)
- Perform a wiggle test of seat harness/connectors while watching live data for the OCS sensor
- Verify battery voltage and perform recommended SRS power-down procedure before working on airbags
- Inspect grounds and power/reference supply to the OCS sensor/module
Signal parameters
- Reference voltage commonly 5 V (check OEM spec); sensor signal typically varies with occupancy
- Power supply to sensor may be switched 12 V or fused feed—verify per vehicle data
- Signal line expected to change value with occupant presence (voltage or resistance change)
- Ground continuity: near 0 ohms to chassis ground
- Communication may be on LIN/CAN or a dedicated analog signal depending on vehicle; compare live-data values to OEM expected ranges
Diagnostic algorithm
- Use a scan tool to read SRS/OCS live data and confirm B2650 is current or historic; record freeze-frame data.
- Disable battery power and wait required time per manufacturer before accessing airbag/seat components.
- Visually inspect the seat cushion area, connectors under the seat, and the occupant sensor mat for obvious damage, water, or contaminants.
- Reconnect and reseat all related connectors; clean contacts if corroded. Ensure connector latches are fully engaged.
- With battery reconnected and scan tool monitoring OCS data, perform a wiggle test of the seat wiring and connectors to look for intermittent changes or return of the code.
- Measure reference voltage, signal voltage and ground at the sensor connector using a DMM and compare to manufacturer specifications.
- Check continuity between the sensor connector and the airbag/OCS control module. Repair any open/shorted wiring found (insulate, replace harness sections, repair terminals).
- If wiring and connectors test normal, measure sensor mat resistance or sensor output per service manual; replace the occupant classification sensor/mat if out of spec.
- If sensor and wiring are good, verify module operation and communications; consider replacement or reprogramming of the OCS/airbag control module only after confirming wiring/sensor faults are not present.
- Clear codes, cycle ignition and retest. Confirm SRS lamp extinguishes and passenger airbag status behaves correctly. Road/test as required.
Likely causes
- Loose or corroded connector under the passenger seat
- Damaged wiring caused by seat movement or abrasion
- Failed occupant classification mat/sensor module
- Intermittent connector contact from contamination or moisture
Fault status
Status
Occupant Classification System sensor circuit malfunction detected. Passenger presence sensor signal out of expected range — inspect seat sensor, wiring, and connectors.
Repair difficulty: Medium
Diagnostic time: 1.0 - 2.5 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