OBD-II Fault Code

B1879: Seatbelt Driver Pretensioner Circuit Short to Ground

Meaning, symptoms, likely causes, diagnostic checks and repair guidance for B1879.

System family

Body

Manufacturer-specific

Repair category

SRS / restraint

Use this category to narrow your checks before replacing parts.

Severity

High

Severity is a general guide. Confirm with scan-tool data and vehicle symptoms.

What B1879 usually means

Seatbelt Driver Pretensioner Circuit Short to Ground.

Common symptoms

Airbag/SRS warning lamp; Safety restraint system may be disabled

Likely causes

Loose SRS connector; Damaged seat/impact sensor wiring; Faulty sensor/module; Low voltage history; Wire shorted to chassis/ground; Internal component short

Diagnostic checks

Check related fuses, connectors, grounds and switch/module power supply; Do not probe SRS wiring with a test light; Check for related service bulletins and connector lock issues; Inspect harness for rubbing/pinch points and check resistance to ground

Repair guidance

Have SRS wiring, sensors and module diagnosed with OEM-level scan tool; Repair connector/wiring faults using approved SRS procedures; Repair insulation/harness damage or replace internally shorted component

Verification after repair

Operate the affected body/accessory system and rescan

Note: Safety-critical: SRS/airbag repairs should be handled by a qualified technician; Manufacturer-specific: confirm definition and test steps in the vehicle service manual. A DTC identifies a circuit or system condition, not always the failed part.