P0500: Vehicle Speed Sensor "A" Malfunction (Meaning, Causes, Fixes)
What P0500 means
The vehicle speed sensor tells the powertrain control module (PCM) how fast the car is moving. RepairPal explains that the reading drives the speedometer and is usually shared with the transmission, ABS, traction control and power steering. OBD-Codes.com describes a typical VSS as an electromagnetic sensor in the transmission housing that reads a toothed reluctor ring on the output shaft. P0500 sets when the PCM sees a speed reading that is missing, inaccurate or not as expected. The sources agree on the definition (Vehicle Speed Sensor "A"), and RepairPal adds that the sensor isn't always on the transmission: it may be at the rear differential, in or near a wheel hub, or attached to the speedometer.
Severity: can I keep driving?
Drive with caution, fix soon
Usually drivable with care, but get it diagnosed soon. RepairPal rates P0500 moderate. Because speed data is shared with the transmission and ABS, OBD-Codes.com notes you may lose anti-lock brakes and get erratic automatic shifting, and your speedometer may read wrong or not at all, so drive gently, leave extra stopping distance and don't rely on the speedometer.
Common symptoms
- Check engine light on
- Speedometer or odometer reading wrong or not working (both sources)
- Erratic or improper automatic transmission shifting (both sources)
- ABS, brake or traction control warning light on, and possible loss of anti-lock braking (OBD-Codes.com; RepairPal mentions ABS and traction control lights)
- Reduced rev limiter (OBD-Codes.com)
- In some cases no noticeable symptoms besides the light (RepairPal)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Faulty vehicle speed sensor (both sources)
- Broken, frayed or damaged wiring or a bad connector to the sensor (both sources)
- PCM not configured for the tire size actually fitted (OBD-Codes.com)
- Faulty speedometer or instrument cluster (RepairPal)
- Communication (CAN) bus problems (RepairPal)
- Worn speed sensor drive gear, or a transmission or differential fault (RepairPal)
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Search for technical service bulletins (TSBs) for your make, model and year first. OBD-Codes.com notes some vehicles, including some Toyotas, have a known bulletin.
- Find where your sensor is mounted (transmission, rear axle or wheel hub, depending on the vehicle) and inspect the wiring and connector for chafing, bare, broken or melted wires.
- If you changed to a different tire or wheel size, mention it to the shop, since a mismatch is one listed cause.
- If the wiring checks out, OBD-Codes.com suggests checking the voltage at the sensor using your vehicle's procedure before replacing it.
Typical fixes
- Repair damaged VSS wiring or connectors
- Replace a faulty vehicle speed sensor
- Reprogram the PCM for the correct tire size where that's the cause
- Repair a faulty speedometer/cluster, CAN bus fault or worn drive gear found by testing
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- RepairPal lists common misdiagnoses: a speedometer problem, an internal transmission problem, an ABS/traction control problem or a driveline problem. A shop with a scan tool can compare the speed reading the PCM sees with other modules to tell these apart.
- Get it checked promptly if the ABS light is on, since anti-lock braking may be disabled until the speed signal is fixed.
- If it comes with transmission codes (such as P0700) or shifting problems, have the transmission side diagnosed too.
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Can a bad speed sensor make my speedometer stop working?
Yes. Both OBD-Codes.com and RepairPal list a speedometer or odometer that reads wrong or not at all as a P0500 symptom, because the speedometer uses the VSS signal.
Will P0500 go away on its own?
RepairPal says most codes clear on their own once the system stops detecting the problem, but if P0500 stays it should be diagnosed to avoid a more serious problem.
How is P0500 different from P0501, P0502 and P0503?
They're all Vehicle Speed Sensor "A" codes. Per OBD-Codes.com, P0501 is range/performance, P0502 is low input and P0503 is intermittent/erratic/high; P0500 is the general malfunction code.
Sources
Last reviewed 2026-10-22. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.