Wheel Speed Sensor A Input Circuit High
Indicates a problem with the front wheel speed sensor A signal.
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 wheel speed sensor A detects how fast the wheel is turning, and it's sending a signal that's too high for the system to handle, making it think there's a problem with the sensor or wiring.
What the computer is actually seeing
The engine control module (ECM) sees a voltage level coming from the wheel speed sensor A that exceeds a defined threshold, typically around 5 volts.
What a healthy reading looks like
The expected signal voltage range for a properly functioning wheel speed sensor is between 0.5 to 3 volts while the vehicle is moving.
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. Start by checking the wiring and connectors at the wheel speed sensor A for physical damage or loose connections. Repair or replace as necessary. Decision: If wiring/connectors are damaged, fix them and retest. If no issues found, proceed to step 2.
- 22. Measure the voltage at the sensor connector with the key on and the engine off. You should see a voltage signal between 0.5V and 3V. Decision: If voltage is outside of this range, replace the speed sensor. If the voltage is within this range, proceed to step 3.
- 33. Inspect the wheel speed sensor itself for any physical damage or corrosion. Clean the sensor if dirty. Decision: If damaged, replace the wheel speed sensor. If clean and intact, proceed to step 4.
- 44. Check for any noise interference in the sensor circuit. Look for sources near the wiring. Decision: If interference is found, eliminate it. If wires test fine and sensor is good, further diagnose the ECM.
Common causes
- Faulty wheel speed sensor A
- Damaged wiring or connectors to the sensor
- Corrosion or debris on the sensor
- Noise interference in the signal circuit
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
It's not recommended to drive until you resolve it, as the ABS and traction control systems rely on accurate speed sensor readings.
Will this code come back after I clear it?
It may come back if there's an underlying issue that's not fixed, like a bad sensor or wiring problem.
Why does this code pair with other C codes?
Codes like C0035 or C0040 are often related to other wheel speed sensors, indicating multiple wheel speed concerns in the system.
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