P0502 fault code: what it means
P0502: Vehicle speed sensor A circuit low input. Speedo, cruise and auto shifting may be affected.
Usual causes, most likely first
- failed speed sensor
- wiring or connector fault
- ABS wheel speed fault on cars that use it
Not sure what P0502 means on your car? Ask Credov.
Before you clear it
Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.
Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.