OBD-II Fault Code

B2118: Passenger Sid, Side mount Airbag Low capacitance on Squib

Meaning, symptoms, likely causes, diagnostic checks and repair guidance for B2118.

System family

Body

Generic/SAE

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 B2118 usually means

Passenger Sid, Side mount Airbag Low capacitance on Squib.

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; Low signal voltage; Weak power supply; High resistance/poor ground; Failed sensor

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; Check sensor reference voltage, ground and signal voltage

Repair guidance

Have SRS wiring, sensors and module diagnosed with OEM-level scan tool; Repair connector/wiring faults using approved SRS procedures; Repair poor ground/power feed or replace confirmed faulty sensor

Verification after repair

Operate the affected body/accessory system and rescan

Note: Safety-critical: SRS/airbag repairs should be handled by a qualified technician. A DTC identifies a circuit or system condition, not always the failed part.