OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Body generic / SAE

B0103

Front Crash Sensor Left Communication Lost

Communication with the left front crash sensor has been lost; SRS deployment logic for frontal impacts is degraded.

SystemBody
Typegeneric / SAE
GroupB0
Range / number1 / 03

Possible causes

  • Open bus wiring high
  • Gateway module routing CAN messages incorrectly low
  • CAN terminating resistor (120 Ω) drifted out of spec low

Symptoms

  • Warning light or symbol related to the affected system
  • Comfort or safety function impaired

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended

What Pro shows you for B0103

Before you go to the garage: roughly what the repair costs, how long it takes and which components are involved.

  • Repair cost (estimate)(visible in Pro mode)
  • Labour time(visible in Pro mode)
  • 2 affected components(visible in Pro mode)
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Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication