B1876

Code

Other B — Body

Seatbelt Driver Pretensioner Circuit Failure

Brand: Other

Type: B — Body

Views: UK: 23 EN: 39 RU: 40

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Page language: EN

Causes

Open circuit in driver pretensioner wiring (broken conductor, damaged insulation, disconnected connector)
Short to ground or short to battery/ignition voltage in pretensioner circuit
Corroded or loose connector at the pretensioner or airbag control module
Faulty driver seatbelt pretensioner (squib)
Faulty SRS/airbag control module or internal driver circuit
Intermittent damage where harness routes through door hinge/seat or under-seat area

Symptoms

SRS/Airbag warning light illuminated on instrument cluster
Stored DTC B1876 in SRS/airbag control module
Possible loss of pretensioner function in a crash (system may disable deployment of affected device)
Inconsistent SRS lamp behavior (comes on at key-on or intermittently)

What to check

Read and record SRS/airbag codes with a capable scan tool; capture freeze frame if available
Check for additional SRS and communication codes (may indicate related faults)
Visually inspect driver seatbelt pretensioner connector and wiring for corrosion, bent pins, loose terminals or damage
Inspect wiring routing through seat base and door hinge area for chafing or pinch points
Check connector at airbag/SRS control module for corrosion or loose pins
Confirm battery voltage and good ground to car body and SRS module (while observing SRS safety procedures)

Signal parameters

Normal squib resistance typically low (example range ~0.5–3.5 ohms) — consult factory service info for exact value for the vehicle
Open circuit: infinite resistance (OL) between pretensioner terminals
Short to ground: continuity between pretensioner circuit and chassis ground
Short to battery/ignition: continuity between pretensioner circuit and vehicle battery positive feed/ignition circuit
Voltage at pretensioner circuit with ignition ON should be near 0V when system is inactive; diagnostic checks performed by SRS tool may measure squib circuit continuity or resistance — follow factory procedures

Diagnostic algorithm

Record all DTCs and freeze frame data with an SRS-capable scan tool; clear codes and perform key-on self-test to see if B1876 returns
Follow manufacturer SRS disable procedure (disconnect battery and wait required time or use service mode) before any hands-on work
Perform visual inspection of driver pretensioner connector, wiring, and routing; repair any obvious damage or corrosion
With SRS disabled per factory procedure, disconnect pretensioner connector and measure resistance across squib terminals with an ohmmeter. Compare to factory spec (typical squib is low ohms). If OL = open circuit, suspect broken wiring or failed squib; if very high resistance, suspect partial break or corrosion
If resistance is within spec, check continuity from pretensioner connector back to SRS module connector pins to identify wiring opens or shorts (backprobe or unplug connectors as required)
Inspect and wiggle harness while monitoring resistance or scan tool live data to find intermittent faults (pay special attention to areas that move: seat tracks, hinges)
If short to ground or power is found, isolate by disconnecting harness sections until fault clears, then repair/replace damaged wiring or connectors
If wiring and connectors test good and resistance out of spec or short persists, replace driver seatbelt pretensioner assembly
After repair, reconnect everything, restore SRS power per manufacturer procedure, clear codes with scan tool and confirm no new or returning DTCs and that SRS lamp behaves normally
If codes persist after component/harness replacement, check SRS control module connectors and grounds; consider module replacement only after exhausting wiring and sensor checks

Likely causes

Damaged connector at seatbelt pretensioner (moisture/corrosion)
Wiring broken or chafed at seat hinge or under-seat brackets
High resistance in pretensioner (partial break or corrosion)
Failed pretensioner squib requiring replacement
Poor ground or power feed at SRS module connector

Fault status

⚠️ Status

Driver seatbelt pretensioner circuit fault detected (open/short/high resistance). SRS warning light set. Pretensioner function may be inhibited until fault is repaired.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.0-3.0 hours