Powertrain, generic · Vehicle speed, idle control and auxiliary inputs
P0501 Vehicle Speed Sensor A Circuit Range/Performance
Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible
The vehicle speed signal A comes, depending on the maker, from a sensor on the gearbox, the transmission output speed, the wheel speeds via ABS/ESP or a CAN message; CARB explicitly names it as an input to be monitored. P0501 means the signal is present but does not fit the driving state or lies outside the physically possible range. Saab's Trionic T5 sets it above 270 km/h; other makers typically compare it with engine speed times gear ratio, wheel speeds or the transmission output speed. GM's 2018 tables and Ford do not use P0501 (GM: P0503, Ford: P0500). Cruise control is then disabled.
Likely causes
Wheel speed sensor or tone ring damaged or dirty (ABS source)
Wrong tyre size, axle ratio or coding
Sensor with weak signal or damaged tone wheel
Interference from damaged shielding or ground
Symptoms
- Check engine light on
- Speedometer dead or jumping
- Cruise control not working
- Automatic shifts harshly or wrongly
Repair estimate
DifficultyMediumDIY possible
Parts and labour€60–350
Time0.5–2 h
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
vehicle speed sensorabs modulesensor wiringengine control module
Related codes
References: saabwisonline.com, saabwisonline.com, law.cornell.edu.