C0027

Left Front Wheel Speed Sensor Signal Erratic

Severity

⚠️ Medium

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

ABS/ESP indicator is on
Uneven operation of ABS
Incorrect speedometer readings (in some models)
Loss of ESP functions

Causes

Wheel speed sensor malfunction
Wiring harness damage
Contamination or damage to the gear ring (rotor)
Lost contact in the connector
Problems with the ABS/ESP module

How to Fix

Visually inspect the sensor and wiring harness for damage
Checking the sensor resistance (compare with factory specifications)
Cleaning the sensor and gear ring from dirt
Checking continuity with an oscilloscope or scanner
If necessary, replace the sensor or repair the wiring harness

Related codes

C0025 C0026 C0028