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B1999 — Right airbag control circuit resistance - low

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Code

B1999

LAND ROVER B — Body

Right airbag control circuit resistance - low

Brand: LAND ROVER
Type: B — Body
Views: UK: 3 EN: 10 RU: 10
AI status
Completed
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Completed 100%
Page language: EN

Causes

  • Short to ground or to another circuit in the right airbag wiring
  • Damaged, chafed, or pinched wiring harness or connector
  • Corroded or contaminated connector terminals
  • Faulty right airbag squib (very low internal resistance or internal short)
  • Incorrect repair or aftermarket equipment tied into the airbag circuit
  • Faulty SRS control module or module connector fault

Symptoms

  • SRS / airbag warning lamp illuminated on dash
  • Passenger/right airbag disabled or unavailable message (if equipped)
  • Possible related SRS codes stored for other right-side restraint devices (seatbelt pretensioner)
  • Vehicle may show SRS fault in live data (fault status, shorted resistance reading)
  • No obvious mechanical symptoms other than warning lamp

What to check

  • Read SRS module for all stored and pending codes and freeze-frame data with a capable scan tool
  • Visually inspect right airbag connector, harness routing, and common wear points (seat, B‑pillar, door jamb)
  • Check for recent repair history (seat removal, interior trim, aftermarket accessories)
  • Measure battery voltage and ensure stable power during diagnosis
  • Confirm there are no other modules offering conflicting data (CAN/SRS communication faults)

Signal parameters

  • Measured circuit resistance (ohms) between SRS module airbag driver pin and squib pin — manufacturer spec required
  • Expected squib resistance typically in the low ohms range (example: ~2–5 Ω for many squibs) — consult Land Rover specs
  • Low-resistance threshold that triggers B1999 will be below the expected range (example:
  • Continuity checks: near-zero ohms to chassis ground suggests short to ground
  • Module sees altered voltage/ground reference on right airbag driver circuit when monitoring

Diagnostic algorithm

  1. Safety first: Disable vehicle battery per manufacturer SRS procedures (disconnect negative terminal and wait the specified time — typically ~90 seconds or as factory procedure states). Use correct PPE and follow safety guidelines to avoid accidental deployment.
  2. Retrieve and record all SRS and related codes and freeze-frame data with a compatible scan tool. Note whether code is current or historic and if other right-side codes are present.
  3. Visually inspect wiring and connectors for the right airbag: passenger seat, seat rails, B-pillar, door jambs, and the area where the harness routes. Look for chafing, pinched wires, melted insulation, or connector corrosion.
  4. With battery disconnected, disconnect the right airbag squib connector (at the squib or intermediate connector) and measure resistance of the squib alone using a digital multimeter. Compare to manufacturer specification. If resistance is abnormally low, suspect squib internal fault.
  5. With squib still disconnected, measure resistance between the SRS module driver pin and chassis ground and between the driver pin and vehicle positive circuits to look for unintended low-resistance paths. If low resistance to ground is present, inspect harness and isolate by unplugging intermediate connectors to localize the short.
  6. If low resistance disappears when a connector is unplugged, inspect and repair the segment between that connector and the next. Repair chafed wires, replace damaged connectors, or re‑terminate pins as required.
  7. If squib measures within spec and no short to ground is found in wiring, consider swapping with a known-good squib (if procedures allow) or inspecting SRS control module connector and pins for damage. Replace module only after wiring and squib are confirmed good.
  8. After repairs, reconnect everything, reconnect battery per procedure, clear codes with scan tool, and verify SRS lamp extinguishes and code does not return. Perform any required SRS system tests or readiness checks per service manual.
  9. If code persists after above steps, consult Land Rover service documentation for module-specific tests and consider module replacement or dealer-level diagnostics.

Likely causes

  • Wiring short where harness passes through body (door jamb, seat base, B-pillar)
  • Connector plugged into squib or module has bent/corroded pins creating a low-resistance path
  • Right side airbag squib has internal short (rare but possible after crash or exposure)
  • Repair shop/previous work left an unintended ground or splice on the circuit

Fault status

⚠️ Status
Right airbag control circuit resistance below expected range. Possible short or connector/wiring fault detected in right-side airbag circuit. SRS lamp illuminated — inspect wiring and squib, repair and verify.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1-3 hours

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Code

B1999

Other B — Body

Passenger Sid, Side mount Airbag Low resistance on Squib

Brand: Other
Type: B — Body
Views: UK: 15 EN: 25 RU: 23
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Short to ground or to another circuit in the right airbag wiring
  • Damaged, chafed, or pinched wiring harness or connector
  • Corroded or contaminated connector terminals
  • Faulty right airbag squib (very low internal resistance or internal short)
  • Incorrect repair or aftermarket equipment tied into the airbag circuit
  • Faulty SRS control module or module connector fault

Symptoms

  • SRS / airbag warning lamp illuminated on dash
  • Passenger/right airbag disabled or unavailable message (if equipped)
  • Possible related SRS codes stored for other right-side restraint devices (seatbelt pretensioner)
  • Vehicle may show SRS fault in live data (fault status, shorted resistance reading)
  • No obvious mechanical symptoms other than warning lamp

What to check

  • Read SRS module for all stored and pending codes and freeze-frame data with a capable scan tool
  • Visually inspect right airbag connector, harness routing, and common wear points (seat, B‑pillar, door jamb)
  • Check for recent repair history (seat removal, interior trim, aftermarket accessories)
  • Measure battery voltage and ensure stable power during diagnosis
  • Confirm there are no other modules offering conflicting data (CAN/SRS communication faults)

Signal parameters

  • Measured circuit resistance (ohms) between SRS module airbag driver pin and squib pin — manufacturer spec required
  • Expected squib resistance typically in the low ohms range (example: ~2–5 Ω for many squibs) — consult Land Rover specs
  • Low-resistance threshold that triggers B1999 will be below the expected range (example:
  • Continuity checks: near-zero ohms to chassis ground suggests short to ground
  • Module sees altered voltage/ground reference on right airbag driver circuit when monitoring

Diagnostic algorithm

  1. Safety first: Disable vehicle battery per manufacturer SRS procedures (disconnect negative terminal and wait the specified time — typically ~90 seconds or as factory procedure states). Use correct PPE and follow safety guidelines to avoid accidental deployment.
  2. Retrieve and record all SRS and related codes and freeze-frame data with a compatible scan tool. Note whether code is current or historic and if other right-side codes are present.
  3. Visually inspect wiring and connectors for the right airbag: passenger seat, seat rails, B-pillar, door jambs, and the area where the harness routes. Look for chafing, pinched wires, melted insulation, or connector corrosion.
  4. With battery disconnected, disconnect the right airbag squib connector (at the squib or intermediate connector) and measure resistance of the squib alone using a digital multimeter. Compare to manufacturer specification. If resistance is abnormally low, suspect squib internal fault.
  5. With squib still disconnected, measure resistance between the SRS module driver pin and chassis ground and between the driver pin and vehicle positive circuits to look for unintended low-resistance paths. If low resistance to ground is present, inspect harness and isolate by unplugging intermediate connectors to localize the short.
  6. If low resistance disappears when a connector is unplugged, inspect and repair the segment between that connector and the next. Repair chafed wires, replace damaged connectors, or re‑terminate pins as required.
  7. If squib measures within spec and no short to ground is found in wiring, consider swapping with a known-good squib (if procedures allow) or inspecting SRS control module connector and pins for damage. Replace module only after wiring and squib are confirmed good.
  8. After repairs, reconnect everything, reconnect battery per procedure, clear codes with scan tool, and verify SRS lamp extinguishes and code does not return. Perform any required SRS system tests or readiness checks per service manual.
  9. If code persists after above steps, consult Land Rover service documentation for module-specific tests and consider module replacement or dealer-level diagnostics.

Likely causes

  • Wiring short where harness passes through body (door jamb, seat base, B-pillar)
  • Connector plugged into squib or module has bent/corroded pins creating a low-resistance path
  • Right side airbag squib has internal short (rare but possible after crash or exposure)
  • Repair shop/previous work left an unintended ground or splice on the circuit

Fault status

⚠️ Status
Right airbag control circuit resistance below expected range. Possible short or connector/wiring fault detected in right-side airbag circuit. SRS lamp illuminated — inspect wiring and squib, repair and verify.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1-3 hours

Similar codes

Your experience will help others
+100 karma for a short comment :)
Send to email