Chassis, generic

C0505 Left Front Wheel Speed Sensor A Correlation

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

C0505 says the left front wheel speed is out of step with the other wheels although the circuit tests pass. GM's 2019 tables (19OBDG03D) group several comparisons under this code: a missing sensor, meaning this wheel shows under 1.5 km/h while another exceeds 6 km/h (3 to 120 s depending on speed); a dropout check paused after sudden accelerations; a start-up check that runs until 15 km/h; and the reverse case, where only this wheel turns. Named causes are a badly seated sensor, an air gap out of tolerance and a demagnetized tone ring. Mitsubishi files speed gaps caused by non-specified tires as C1061-64 = C0505, evaluated between 10 and 60 km/h. For comparison, Toyota decides wheel sensor plausibility from about 6 mph, as FenderBender explains.

Likely causes

Tire of a different size or heavily worn tire on the left front
Sensor not seated correctly, air gap out of tolerance
Demagnetized or damaged magnetic encoder ring

Symptoms

  • ABS/ESC lamps after a drive, often following a tire change
  • Traction control intervenes although wheels are not slipping

Repair estimate

DifficultyEasyDIY possible
Parts and labour€0–400
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

wss lftone ring lftires

Related codes

C0500C0501C0504C050BC053CC0555

References: gsi.ext.gm.com, mitsubishitechinfo.com, fenderbender.com.