Toggle Side Panel

Shopping Cart

No products in the basket.

Shopping Cart

No products in the basket.

Close search
Home / DTC / B1A19 — Occupant Classification System (OCS) Fault

B1A19 — Occupant Classification System (OCS) Fault

Detailed page for trouble code B1A19.

34,405codes
59brands
11,914generic
22,491specific
All codes P-codes (Powertrain) B-codes (Body) C-codes (Chassis) U-codes (Network/User) Tesla Alerts
Reset
Code

B1A19

Generic B — Body

Occupant Classification System (OCS) Fault

Brand: Generic
Type: B — Body
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or disconnected seat occupancy sensor mat or harness
  • Water intrusion or corrosion in seat connectors or mat
  • Faulty OCS control module or sensor electronics
  • Open/short in power, ground, or signal wiring to the OCS
  • Loss of CAN/LIN communication between OCS and airbag/BCM modules
  • Incorrect or lost OCS calibration or software mismatch

Symptoms

  • Airbag warning lamp illuminated (SRS/airbag DTC indicator)
  • Message on dash about passenger airbag 'OFF' or 'Service Occupant Classification System'
  • Passenger airbag enabling/disabling incorrectly or unpredictably
  • Possible stored multiple OCS-related DTCs or communication DTCs
  • Inability to complete OCS calibration or re‑learn procedure

What to check

  • Read stored DTCs and freeze frame with a capable scan tool; record all related codes and timestamps
  • Check for additional communication codes (U0121, U0155, etc.) that may indicate bus issues
  • Visually inspect seat bottom and back: connectors, clips, wiring harness routing and protective sleeves
  • Inspect connectors under seat for corrosion, water, damaged pins, or loose terminals
  • Check for signs of water intrusion or contamination in the seat cushion or mat
  • Verify occupant sensor mat is correctly positioned and not creased or damaged

Signal parameters

  • OCS module power supply voltage (typically ignition-switched 12 V) — verify present and stable
  • OCS module ground continuity to chassis — low ohm connection
  • Sensor mat resistance or capacitance vs. specification — measure as instructed by service manual
  • Diagnostic trouble code status, freeze frame data and related PID/live-data values for passenger presence
  • CAN/LIN bus data: OCS module message frequency and status (messages present, error counts)
  • Signal voltage levels on sensor lines if applicable (0–5 V logic levels typical)

Diagnostic algorithm

  1. Connect a diagnostic scan tool that supports the OCS and retrieve all DTCs and live data; note any related communication codes.
  2. Record passenger presence/live sensor values with no occupant, a known-weight test object and with a normal passenger to observe expected changes.
  3. Visually inspect seat area and connectors; secure or re‑seat any loose connectors. Look for water, corrosion and damaged wires.
  4. With battery disconnected per manufacturer safety procedures, inspect the sensor mat for physical damage and verify connector pins and terminals.
  5. Check power and ground at the OCS module (or SRS module interface) with key on; verify proper voltages and good ground. Repair any poor connections.
  6. Perform continuity/resistance/capacitance checks on the sensor mat and wiring per service manual. Compare to specification or known-good reading.
  7. If bus communication is suspect, check CAN/LIN wiring, termination resistors and related modules for errors; resolve bus faults first.
  8. If wiring and connectors are good but sensor readings are out of range, replace or repair the sensor mat assembly.
  9. If sensor mat and wiring are good, consider module reprogramming or replacement; perform manufacturer OCS calibration/relearn procedure after repairs.
  10. Clear codes, perform relearn/calibration, and verify system operation and that codes do not return during functional test and road test.

Likely causes

  • Connector(s) under seat disconnected, dirty, or corroded
  • Damaged sensor mat (tears, water damage) or broken continuity in mat traces
  • Faulty module supplying or reading the OCS sensors (power, ground, reference)
  • Intermittent wiring fault caused by seat movement or broken pin at connector
  • Failed/incorrect OCS re‑learn or calibration after seat removal or repair

Fault status

⚠️ Status
OCS Fault (B1A19): Occupant Classification System error detected. Passenger presence classification unavailable or unreliable. Service required — inspect seat sensors, connectors, wiring, module communication and perform OCS calibration.
🔴 Repair difficulty: Hard
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

B1A18 B1A1A B1A1B B1A20 U0121
9,396

The library contains 9,396 repair and diagnostic manuals. Choose a brand to open the full manual tree by year, model and trim.

ALFA ROMEO
89
AUDI
1,243
BMW
479
CADILLAC
206
CHEVROLET
456
CHRYSLER
193
DAEWOO
75
FIAT
26
GENESIS
207
HUMMER
138
HYUNDAI
371
ISUZU
53
KIA
155
LAND ROVER
320
LEXUS
280
LINCOLN
166
MERCEDES-BENZ
856
MERCURY
296
MITSUBISHI
406
PORSCHE
136
TESLA
58
TOYOTA
2,209
TRIUMPH
131
VOLKSWAGEN
626
VOLVO
221
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

B1A19

LAND ROVER B — Body

Body Control Module Internal Fault

Brand: LAND ROVER
Type: B — Body
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Damaged or disconnected seat occupancy sensor mat or harness
  • Water intrusion or corrosion in seat connectors or mat
  • Faulty OCS control module or sensor electronics
  • Open/short in power, ground, or signal wiring to the OCS
  • Loss of CAN/LIN communication between OCS and airbag/BCM modules
  • Incorrect or lost OCS calibration or software mismatch

Symptoms

  • Airbag warning lamp illuminated (SRS/airbag DTC indicator)
  • Message on dash about passenger airbag 'OFF' or 'Service Occupant Classification System'
  • Passenger airbag enabling/disabling incorrectly or unpredictably
  • Possible stored multiple OCS-related DTCs or communication DTCs
  • Inability to complete OCS calibration or re‑learn procedure

What to check

  • Read stored DTCs and freeze frame with a capable scan tool; record all related codes and timestamps
  • Check for additional communication codes (U0121, U0155, etc.) that may indicate bus issues
  • Visually inspect seat bottom and back: connectors, clips, wiring harness routing and protective sleeves
  • Inspect connectors under seat for corrosion, water, damaged pins, or loose terminals
  • Check for signs of water intrusion or contamination in the seat cushion or mat
  • Verify occupant sensor mat is correctly positioned and not creased or damaged

Signal parameters

  • OCS module power supply voltage (typically ignition-switched 12 V) — verify present and stable
  • OCS module ground continuity to chassis — low ohm connection
  • Sensor mat resistance or capacitance vs. specification — measure as instructed by service manual
  • Diagnostic trouble code status, freeze frame data and related PID/live-data values for passenger presence
  • CAN/LIN bus data: OCS module message frequency and status (messages present, error counts)
  • Signal voltage levels on sensor lines if applicable (0–5 V logic levels typical)

Diagnostic algorithm

  1. Connect a diagnostic scan tool that supports the OCS and retrieve all DTCs and live data; note any related communication codes.
  2. Record passenger presence/live sensor values with no occupant, a known-weight test object and with a normal passenger to observe expected changes.
  3. Visually inspect seat area and connectors; secure or re‑seat any loose connectors. Look for water, corrosion and damaged wires.
  4. With battery disconnected per manufacturer safety procedures, inspect the sensor mat for physical damage and verify connector pins and terminals.
  5. Check power and ground at the OCS module (or SRS module interface) with key on; verify proper voltages and good ground. Repair any poor connections.
  6. Perform continuity/resistance/capacitance checks on the sensor mat and wiring per service manual. Compare to specification or known-good reading.
  7. If bus communication is suspect, check CAN/LIN wiring, termination resistors and related modules for errors; resolve bus faults first.
  8. If wiring and connectors are good but sensor readings are out of range, replace or repair the sensor mat assembly.
  9. If sensor mat and wiring are good, consider module reprogramming or replacement; perform manufacturer OCS calibration/relearn procedure after repairs.
  10. Clear codes, perform relearn/calibration, and verify system operation and that codes do not return during functional test and road test.

Likely causes

  • Connector(s) under seat disconnected, dirty, or corroded
  • Damaged sensor mat (tears, water damage) or broken continuity in mat traces
  • Faulty module supplying or reading the OCS sensors (power, ground, reference)
  • Intermittent wiring fault caused by seat movement or broken pin at connector
  • Failed/incorrect OCS re‑learn or calibration after seat removal or repair

Fault status

⚠️ Status
OCS Fault (B1A19): Occupant Classification System error detected. Passenger presence classification unavailable or unreliable. Service required — inspect seat sensors, connectors, wiring, module communication and perform OCS calibration.
🔴 Repair difficulty: Hard
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

B1A18 B1A1A B1A1B B1A20 U0121
320

Browse 320 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email

Report

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .