Wheel Speed Sensor Circuit Malfunction (Left Front)
Indicates a problem with the left front wheel speed sensor circuit.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The left front wheel speed sensor is either not sending a signal or is sending an incorrect one, which affects traction control and ABS operation.
What the computer is actually seeing
The engine control module (ECM) expects to see a regular voltage signal from the wheel speed sensor that fluctuates based on wheel rotation speed, typically between 0-5 volts. If no signal or an erratic signal is detected, the code is triggered.
What a healthy reading looks like
A properly functioning wheel speed sensor should generate a voltage signal that varies from 0 to 5 volts in sync with wheel speed during vehicle operation, ideally showing a fluctuating waveform on an oscilloscope.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the wiring and connector at the left front wheel speed sensor for damage or corrosion. If damaged, repair or replace and retest.
- 22. Measure the voltage at the wheel speed sensor connector with the key on, engine off. Expected voltage should be around 5V. If no voltage, check wiring back to the ECM.
- 33. If voltage is present, use a multimeter or oscilloscope to check the signal output from the sensor while rotating the wheel. A consistent signal should be seen. If no signal, replace the sensor and retest.
- 44. After replacing the sensor, clear the code and perform a road test to see if the code reappears.
Common causes
- Damaged wire or connector in the wheel speed sensor circuit
- Faulty wheel speed sensor
- Corrosion in the sensor connector
- Faulty ABS module
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with code C0220?
It's not safe to drive with this code as it affects ABS and traction control functionality.
Will this code come back after clearing?
Yes, if the underlying issue isn't fixed, the code will return.
Why does this code pair with others like C0221?
Related codes indicate issues with other wheel speed sensors and suggest a broader problem in the ABS system.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →