Vehicle Speed Sensor A Malfunction
What it means
The engine computer has detected a problem with the vehicle speed signal: it is missing or implausible while the vehicle is moving. Many systems rely on this signal, including the speedometer, transmission shifting and cruise control, so the effect often shows up in more than one system.
Related lights
Dashboard lights that may come on with this code.
Symptoms5
- Speedometer does not move or jumps around.
- Harsh or late automatic transmission shifts, or the transmission stays in one gear.
- Cruise control stops working.
- Check engine light on, and on some vehicles the ABS light as well.
- Odometer may stop recording distance.
Possible causes6
- Failed vehicle speed sensor.
- Broken or corroded sensor wiring or connector.
- Metal debris or dirt on the magnetic sensor tip.
- Damaged tone ring or sensor drive gear in the transmission.
- Faulty wheel speed sensors or ABS module on vehicles that take speed from them.
- Fault in the engine computer or another module that shares the speed signal (rare).
How to diagnose5
- Read all codes in the engine, transmission and ABS modules to learn where this vehicle gets its speed signal.
- Watch vehicle speed on a scan tool while driving and compare it with wheel speeds if available.
- Inspect the sensor connector and wiring for breaks, corrosion or chafing.
- Check the sensor signal with a meter or oscilloscope while turning the wheels, and compare it with the manufacturer specification.
- Remove the sensor and inspect its tip and the condition of the tone ring or gear.
How to fix5
- Clean metal debris off the sensor tip and reinstall it securely.
- Repair damaged wiring or the connector.
- Replace the faulty vehicle speed sensor or wheel speed sensor.
- Replace the tone ring or drive gear if damaged.
- Clear the codes, then road test and confirm the speedometer works and the code does not return.
Repair cost
In Saudi riyals; the highlighted part is the expected range for this fault.
In the Saudi market: SAR 100–700 (≈ USD 27–187)
Our prices come from the Saudi market, converted at a fixed rate (SAR 3.75 per USD). Prices in your country may differ a lot, so we show the cost level.
The cost is low when the cause is wiring or a dirty sensor, and rises when the sensor or tone ring must be replaced, especially if parts of the transmission or axle must be removed to reach it.
Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026
Frequently asked questions
Why does this code affect the transmission?
The transmission computer uses vehicle speed to time shifts. Without the signal it may enter a protection mode, shifting harshly or staying in one gear.
Can I drive with this code?
For short distances and with care. The speedometer may be wrong and driver aids may not work, so repair it soon.
Could the cause be in the ABS system?
Yes, on many modern vehicles, because vehicle speed is calculated from the wheel speed sensors and sent by the ABS module, so check its codes too.
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