OBD Guide

C1233

Left Front Wheel Speed Sensor Input Signal Missing

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$33–167 (est.)

Symptoms

  • The ABS indicator on the dashboard is on
  • Disabling the ABS system
  • Possible false alarms of the stabilization system (if any)

Causes

  • Open or shorted sensor wiring harness
  • Wheel speed sensor malfunction
  • Damage or oxidation of the sensor connector
  • Problems with the gear ring (dirt, damage)
  • ABS module malfunction

How to Fix

  1. Check the integrity of the sensor wiring harness
  2. Inspect the sensor connector for damage and oxidation.
  3. Check sensor resistance (usually 800-2500 Ohm)
  4. Clean the toothed ring from dirt
  5. If necessary, replace the wheel speed sensor

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