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SensorsSeverity Medium: diagnose soon

P0502Vehicle Speed Sensor "A" Circuit Low Input

What it means

The vehicle speed signal is too low or missing while the car is moving.

Symptoms

  • Speedometer not working or jumping
  • Erratic or no shifting on automatics
  • ABS or cruise control warnings

Common causes

  • Open or shorted sensor wiring
  • Failed sensor
  • Connector corrosion

What to check first

  1. Check the signal while driving or on a lift with the wheels turning
  2. Check wiring and connector
  3. Compare with ABS wheel speeds
Can I drive with P0502? Usually yes for a short distance, but performance or economy may suffer and the fault can get worse. Diagnose it soon.

Generic OBD-II meaning. Manufacturer-specific meanings and checks can differ; always check the service information for the car.

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P0502: questions and answers

What does P0502 mean?

P0502: Vehicle Speed Sensor "A" Circuit Low Input. The vehicle speed signal is too low or missing while the car is moving.

What are the symptoms of P0502?

Speedometer not working or jumping. Erratic or no shifting on automatics. ABS or cruise control warnings.

What causes P0502?

Open or shorted sensor wiring. Failed sensor. Connector corrosion.

How do you diagnose P0502?

1. Check the signal while driving or on a lift with the wheels turning 2. Check wiring and connector 3. Compare with ABS wheel speeds

Can I drive with P0502?

Usually yes for a short distance, but performance or economy may suffer and the fault can get worse. Diagnose it soon.