P0500 — Vehicle Speed Sensor 'A' Malfunction
Moderate severityWhat it means
The engine control unit is receiving no vehicle speed signal, or one that does not match other data. Speed input is used by the transmission, ABS, cruise control and instrument cluster, so several systems can misbehave at once.
Common symptoms
- Speedometer dead or erratic
- Harsh or incorrect automatic transmission shifting
- ABS or traction control warning lights
- Cruise control refusing to engage
Likely causes
- Failed vehicle speed sensor
- Damaged wiring or connector at the transmission
- Faulty instrument cluster
- On some cars: a failed ABS wheel-speed sensor feeding the signal
What to check first
- Compare the speed reading in live data with GPS speed while driving
- Inspect the sensor connector at the transmission output
- Check wiring for chafing near the exhaust or suspension
- Read ABS codes — a wheel-speed sensor fault may be the source
Can you keep driving?
Drivable with care, but shifting and ABS behaviour may be affected — diagnose soon.
Scan, log and diagnose with MechanicAI
Plug a Bluetooth OBD2 adapter into your car and let MechanicAI turn raw data into answers:
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- And above all — analyze it all with AI for the most likely cause and clear next steps.
Related codes
All information, explanations and guidance on this page are general preliminary information only. They are estimates and may be entirely wrong, incomplete or inaccurate, or may not apply to your vehicle at all. Never take any action based on this content alone — do not decide to keep driving, clear codes, replace parts, repair or otherwise work on your vehicle based only on what you read here. In every case, and for any final decision, you must consult qualified technical personnel (a professional mechanic, an authorized service centre or an engineer) and obtain their approval before acting. MechanicAI accepts no liability or responsibility whatsoever for any damage, fault, injury, loss or outcome that may arise — directly or indirectly — from using or relying on this information, for any reason and under any circumstances. By using this page you acknowledge and accept these terms.