B1880

Code

Other B — Body

Seatbelt Passenger Pretensioner Circuit Failure

Brand: Other

Type: B — Body

Views: UK: 33 EN: 39 RU: 26

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Page language: EN

Causes

Open or shorted wiring in the passenger pretensioner circuit
Corroded or loose connector at the pretensioner or SRS ECU
High-resistance connection in the harness (intermittent contact)
Failed passenger seatbelt pretensioner (internal short or open)
Faulty airbag/SRS control module or internal driver
Damage from a previous crash or improper repair

Symptoms

SRS/airbag warning light illuminated on dash
Seatbelt warning indicator may be lit or show a fault
Passenger pretensioner will not arm or operate
Possible stored crash event history or related SRS codes
Intermittent faults or faults that reappear after clearing codes

What to check

Read SRS module with a capable scan tool; record freeze-frame and stored DTCs
Visually inspect passenger seat area, seat base, and harness for damage or loose connectors
Check vehicle history for prior deployment or repairs to the seat/airbag system
Inspect connector terminals for corrosion, bent pins, or pushed-out terminals
Verify occupant classification/seat occupancy sensor operation if equipped
Confirm no aftermarket accessories (seat heaters, power seats) have damaged wiring

Signal parameters

Typical pretensioner coil resistance: low value (commonly around 0.5–3 ohms) — consult vehicle service data for exact spec
Open-circuit indication: very high resistance (kΩ range) or infinite
Short-to-ground indication: near 0 ohms between circuit and chassis ground
Short-to-power indication: low resistance between circuit and battery +
On KEY-ON (engine off), SRS ECU should show nominal pretensioner circuit status; voltage to pretensioner typically present only when commanded by ECU — check live data with scan tool

Diagnostic algorithm

Use an SRS-capable scan tool. Read and record all SRS/airbag codes, freeze-frame data and deployment history.
Review service manual for the specific vehicle: obtain wiring diagrams, connector views, and resistance/power/ground specifications for the passenger pretensioner circuit.
Visually inspect the passenger seat, seat track, and harness routing for chafing, pinched wires, or damage. Inspect connector at pretensioner and SRS ECU.
Follow the manufacturer's SRS disable procedure (disconnect battery and observe required wait time) before unplugging connectors or measuring resistance on the pretensioner device.
With SRS disabled, measure resistance across the pretensioner terminals at the connector. Compare to service data (typical low-Ω value). An open or very high reading indicates an open or disconnected pretensioner; a short to ground/power can be checked by measuring resistance to chassis ground and to battery +.
If resistance is out of spec, inspect wiring continuity back to the ECU. Wiggle harness and connectors while monitoring signal/resistance to find intermittent faults.
If wiring and connectors are good but resistance is abnormal, replace the pretensioner assembly per manufacturer procedure.
If wiring and pretensioner check OK, verify SRS ECU power, ground and internal diagnostics. Replace or reprogram ECU only after confirming external wiring and devices are good and following manufacturer guidance.
After repairs, reconnect and enable SRS, clear codes with the scan tool, and perform SRS system readiness checks and a final scan to confirm no recurring faults.
If the fault persists or crash data is present, consult manufacturer technical service bulletins or dealer-level diagnostics.

Likely causes

Broken or pinched conductor in the seat harness (wheel well/seat track area)
Connector pin corrosion or bent/missing terminal at pretensioner or ECU
Pretensioner already deployed or internally failed
Short to ground or battery voltage due to damaged insulation
Faulty SRS control module reporting erroneous circuit fault
Aftermarket seat or repairs that disturbed factory wiring

Fault status

⚠️ Status

Passenger seatbelt pretensioner circuit fault detected — circuit open/short/high resistance or pretensioner failure. SRS warning lamp set; passenger pretensioner may be disabled.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours