01 People Admit They Ignored This Strange Noise Until Their En… • 02 The SR-71 Blackbird: Flying at Mach 3.3, what do pilots fee… • 03 P0172 – System Too Rich (Bank 1): Fuel Economy Problems • 04 10 Abbreviations for Sensors Used in Cars • 05 Sensing the Power: A Comprehensive Guide to Automatic Trans… • 06 Why Is My Car Blowing White Smoke? Don't Ignore These Red F… • 07 Mechanics Shocked At How Many Cars Are Destroyed By Owners … • 08 Fuel Injectors: A Comprehensive Guide to Their Anatomy, Fun… • 09 ELECTRIC PARKING BRAKES (EPB): COMPONENTS, WORKING PRINCIPL… • 10 This Is Why Your Car’s Rear Passengers Are Protected •

DTC codes / B00xx · Airbags, seats, doors, lights and comfort systems / B0093

B0093Side Impact Sensor Left Front Communication Lost

B0093 means the restraint control module has lost communication with the left front side impact sensor, so it cannot receive crash data from that sensor. The module sets the code when the sensor's signal is missing, intermittent, or outside the expected range during its self-test.

SystemBody
Code typeGeneric (all makes)
SeverityHigh
Fix difficultyProfessional
AreaAirbags, seats, doors, lights and comfort systems

Symptoms you may notice

  • The airbag or supplemental restraint system (SRS) warning light stays on after the bulb check.
  • A message such as 'Service Airbag' or 'Restraint System Fault' appears in the driver information center.
  • The SRS system may be disabled, so airbags and seat belt pretensioners will not deploy in a crash.
  • Often no symptoms besides the warning light, because the fault is in a sensor circuit that does not affect normal driving.
  • In some vehicles, remote start or other features tied to the restraint system may be inhibited.

Common causes, most likely first

  1. A damaged or disconnected left front side impact sensor connector, often from collision repair or interior work.
  2. A chafed, pinched, or broken wire in the left front sensor circuit, commonly at the door hinge area or under the seat.
  3. Corrosion or water intrusion at the sensor connector or in the harness, especially on vehicles with sunroof drains or door seal leaks.
  4. A failed left front side impact sensor itself, either internally open or shorted.
  5. A faulty restraint control module (RCM) that cannot communicate on the sensor bus, though this is less common.
  6. Low battery voltage or a charging system problem that causes the RCM to drop sensor communication during cranking.
  7. Aftermarket accessories or previous repairs that disturbed the SRS harness or mounting points.

How to diagnose and fix it

  1. Verify battery voltage and charge the battery if needed, then clear the code and recheck to see if it returns immediately.
  2. Inspect the left front side impact sensor connector for looseness, corrosion, or pushed-out terminals, and reseat it firmly.
  3. Trace the sensor harness from the sensor to the RCM, looking for chafing, pinches, or breaks at the door hinge and under the seat.
  4. Measure resistance and continuity on the sensor circuit with a digital multimeter (DMM) and compare to the manufacturer's specification.
  5. Substitute a known-good sensor of the same part number or use a signal simulator to confirm whether the fault follows the sensor or the wiring.
  6. If the circuit and sensor test good, check for communication faults on the sensor bus and inspect the RCM connectors and grounds.
  7. After repair, clear codes, perform the required SRS calibration or learn procedure, and verify the warning light stays off through several drive cycles.

What the side sensor code really tells you

  • A side impact sensor is a satellite on a dedicated serial data bus, so a communication loss often points to wiring or a connector rather than the sensor itself.
  • The sensor is usually mounted inside the B-pillar or under the front seat, and interior work such as seat removal or trim replacement frequently disturbs its connector.
  • Water leaks from a clogged sunroof drain or a failed door seal can corrode the connector and set this code long before the sensor fails electrically.
  • A weak battery or poor ground can cause the RCM to log this code intermittently, so always check charging system health before condemning parts.
  • This code does not always mean the sensor is dead; a loose connector or a chafed wire at the door hinge is a far more common cause.

Can I keep driving with B0093?

The vehicle is not safe to drive because the side airbag and seat belt pretensioner on that side may not deploy in a crash. Have the fault repaired before driving, and avoid any situation that could trigger a side impact until the SRS light is off.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage