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. P0500 is the general code for this signal. Ford checks plausibility: the car must be moving (high load, positive torque), yet the signal stays below 1–5 mph for 5 s; Ford diesels flag a missing CAN message after 0.5 s. GM's Saturn ION of 2004 used high load with below 3 mph for 6.2 s (MIL after two trips); GM's 2018 tables use P0502/P0503 instead. Cruise control is then disabled and substitute values are used.
Medium severity. Can I keep driving?You can drive carefully to a repair shop, but without a reliable speedometer you cannot control your speed and the automatic transmission may behave oddly. If ABS or stability control warning lights also come on, assume those aids are off and allow extra braking distance.
Symptoms
- Check engine light on
- Speedometer dead or jumping
- Cruise control not working
- Automatic shifts harshly or wrongly
Most likely causes
- ABS/ESP module or wheel speed sensor faulty (signal source)
- Output speed sensor or vehicle speed sensor faulty or dirty (metal debris on the magnet)
- Wire or connector open or shorted, corrosion
- CAN communication fault (message missing)
- Wrong tyre or axle data programmed
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It can trigger limp mode.
- It affects emissions.
What each character of P0500 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 5: Speed and idle
- 00: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0500?
You can drive carefully to a repair shop, but without a reliable speedometer you cannot control your speed and the automatic transmission may behave oddly. If ABS or stability control warning lights also come on, assume those aids are off and allow extra braking distance.
What causes code P0500?
The most common causes are: aBS/ESP module or wheel speed sensor faulty (signal source); output speed sensor or vehicle speed sensor faulty or dirty (metal debris on the magnet); wire or connector open or shorted, corrosion.
Related codes
- P0501Vehicle Speed Sensor A Circuit Range/Performance
- P0502Vehicle Speed Sensor A Circuit Low
- P0503Vehicle Speed Sensor A Circuit Intermittent/Erratic/High
- P0720Output Shaft Speed Sensor Circuit
- P0715Input/Turbine Shaft Speed Sensor A Circuit
- P0571Brake Switch A Circuit
Sources
- newtonnet.co.uk: fordobd2012
- fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023
- fordservicecontent.com: obd summary diesel 2023
- gsi.ext.gm.com: 2004file1
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.