B0091 on GMC: Symptoms, Causes & Fix
Official technical diagnostic wire for fault code B0091 specifically affecting GMC vehicles (Sierra 1500, Yukon, Acadia, Canyon, Terrain).
Select Your GMC Model for B0091:
1. Common Symptoms on GMC Vehicles
When GMC Engine Control Modules (ECM) trigger fault code B0091, drivers typically report:
2. Root Causes on GMC Engines
Historical diagnostic claims across GMC engines point to the following failure distribution:
3. Step-by-Step Fix Protocol for GMC
Disconnect battery negative cable and wait 15 minutes to fully discharge SRS backup capacitors before touching airbag components. on GMC engines.
Remove driver side door sill trim / lower B-pillar trim to access the yellow impact sensor. on GMC engines.
Inspect sensor for water corrosion or cracked plastic housing. on GMC engines.
Bolt new OEM side impact sensor into clean, rust-free ground location, torque bolt to spec, and click yellow locking connector firmly. on GMC engines.
Reconnect battery, clear SRS trouble codes with an airbag-capable scanner, and verify light turns off after 5-second bulb check. on GMC engines.
Equipment for Diagnosing GMC (B0091)
GMC OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for GMC.
AstroAI Auto-Ranging Digital Multimeter
Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.
BlueDriver Bluetooth Pro OBDII Scan Tool
Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.
4. GMC B0091 Frequently Asked Questions
What does code B0091 mean on a GMC?
On GMC vehicles, B0091 indicates that the Engine Control Module (ECM) detected left side restraints sensor 1. This typically points to Corroded or damaged left side impact crash sensor (B-pillar or door sill) or Corroded wiring harness under driver seat / driver door sill.
Can I continue driving my GMC with code B0091?
Caution. Side curtain and seat airbag deployment may be disabled in a side-impact collision. Because this code carries a Critical severity rating on GMC powertrains, we recommend scanning live data values promptly to prevent secondary damage.
How much does it cost to fix code B0091 on a GMC?
Estimated DIY parts cost ranges from $150 - $450 (DIY: $60 - $180), while professional shop repairs at an authorized GMC dealership or independent specialist typically range from $180 to $380 including diagnostic labor.