Engine-Codes - GMC - B0091 GMC

B0091 GMC Code - Center Front Impact Sensor

- Code Popularity: 13,330 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents

|What are the Possible Causes of the Code B0091 GMC?

  • Faulty Center Front Impact Sensor
  • Center Front Impact Sensor harness is open or shorted
  • Center Front Impact Sensor circuit poor electrical connection
  • Faulty Inflatable Restraint Sensing and Diagnostic Module (SDM)

|How to Fix the B0091 GMC Code?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

|Code B0091 GMC Tech Notes

B0091:01 Center Front Impact Sensor Short to Battery
B0091:02 Center Front Impact Sensor Short to Ground
B0091:05 Center Front Impact Sensor Short to Battery or Open
B0091:0F Center Front Impact Sensor Erratic
B0091:39 Center Front Impact Sensor Internal Electronic Failure
B0091:3A Center Front Impact Sensor Incorrect Component Installed
B0091:71 Center Front Impact Sensor Invalid Serial Data Received

|What is the Cost to Diagnose the Code B0091 GMC?

Labor: 1.0

The cost to diagnose the B0091 GMC code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

Does your GMC have Safety Recalls? → Check here

|What are Code B0091 GMC Possible Symptoms?

  • Air Bag Warning Light ON

|What Does the B0091 GMC Code Mean?

The impact sensors are equipped on vehicles to supplement the Supplemental Inflatable Restraint (SIR) system performance. The impact sensors are electronic and are not part of the deployment loops, instead, they provide inputs to the Inflatable Restraint Sensing and Diagnostic Module (SDM). The impact sensors can assist in determining the severity of some frontal and side collisions. The inflatable restraint sensing and the diagnostic module use the input from the impact sensors to assist in determining the severity of a collision, further supporting air bag deployment. If the inflatable restraint sensing and diagnostic module determine a deployment is warranted, the inflatable restraint sensing and diagnostic module will cause current to flow through the deployment loops deploying the appropriate air bags. The center front impact sensor and side impact sensors utilize a bidirectional 2-wire circuit. The sensors modulate current on the interface to send identification, state of health, and deployment commands to the inflatable restraint sensing and diagnostic module. The inflatable restraint sensing and diagnostic module serve as a power source and a ground for the sensors. When the ignition is turned ON and input power from the inflatable restraint sensing and the diagnostic module is first detected, the sensors respond by performing internal diagnostics and sending identification to the inflatable restraint sensing and diagnostic module. The inflatable restraint sensing and diagnostic module consider the identification to be valid if the response time is less than 5 s. The sensors continually communicate status messages to the inflatable restraint sensing and diagnostic module, which determines if a fault is present in the sensor circuit. When a fault is detected, the inflatable restraint sensing and diagnostic module may reset the sensors up to 2 times by removing and reapplying power to it. If the fault is still present, the inflatable restraint sensing and diagnostic module will set a Diagnostic Trouble Code (DTC).

B0091 GMC Code - Center Front Impact Sensor

|Need more Information on the B0091 GMC Code?

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|Need Help with the B0091 GMC Code?

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Precautions for SRS “AIR BAG” and “SEAT BELT PRE-TENSIONER” Service

  • Never probe the electrical connectors on air bag, side air curtain modules or seat belts.
  • Never disassemble or tamper with safety belt buckle/retractor pretensioners, adaptive load limiting retractors, safety belt inflators, or probe the electrical connectors.
  • Do not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
  • Before servicing the SRS, turn ignition switch OFF, disconnect both battery cables and wait at least 3 minutes. For approximately 3 minutes after the cables are removed, it is still possible for the air bag and seat belt pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes have passed.
Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.