P0500 fault code: vehicle speed sensor fault
Plain-language definition
Vehicle Speed Sensor A Circuit
What does it mean?
The engine computer learns how fast the car is going from a speed signal. On older cars this signal usually comes from a separate speed sensor on the transmission; on many newer cars it's calculated from the ABS wheel speed sensors and shared over the data network (CAN). This information is used by many functions, such as the speedometer, automatic transmission gear shifts, idle control and cruise control.
If engine speed and load show that the car is moving but no speed signal arrives, or the signal changes in an implausible way, the engine computer stores P0500. Some manufacturers define this code as a consistency check of the speed signal coming over the data network; on those cars the problem may lie more with the ABS or the data network than with a sensor.
You may notice the speedometer not working or its needle jumping around, harsh or erratic gear shifts in an automatic transmission, cruise control not working, rough idling or the engine stalling when the car stops. If the speed information comes from the ABS, the ABS or ESP warning light may also come on.
How serious is it?
It's rated Warning, but because many systems use the speed information, the effects can be wide-ranging: gear shifts, the speedometer and driver assistance systems may not work properly.
Severity is a guide; if the warning light is flashing or you notice symptoms while driving, have the car checked at a workshop.
Common general causes
- A failed speed sensor, or one fouled with metal dust
- A break, a loose connection or corrosion at the sensor's connector or in its wiring
- If the speed information comes from the ABS, a problem with the wheel speed sensors or the ABS unit
- Damage to the gear or ring the sensor reads
- Less often, a fault in the instrument cluster, the data network (CAN) or the engine computer
The list shows general causes; a workshop finds the actual cause on your car with a check.
Definitions by make
Some manufacturers record the same code under their own wording:
- Fiat
- Vehicle speed signal from CAN, Plausibility
Related codes
How does it appear in the 2dakika report?
Vehicle Speed Sensor A Circuit
If the code is read as a confirmed (stored) fault, the report shows it with the "Warning" severity; in pending or past records, codes that don't request the warning light and aren't critical appear as "Info". If the engine computer stored them, the conditions when the fault was recorded (engine temperature, rpm, speed) are shown too.
Read this code with the OBD-X1, and clear it from the app after the repair.
Clearing the code doesn't fix the fault; if the problem persists, the code comes back.