Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with a sensor in your car that tells how fast you're going. It's not working right all the time.
The vehicle speed sensor (VSS) provides information to the car's computer about how fast the vehicle is moving. Code P0503 indicates that the signal from this sensor is inconsistent or too high.
The P0503 code is triggered when the powertrain control module (PCM) detects an intermittent, erratic, or excessively high signal from the vehicle speed sensor A. This can affect the vehicle's speedometer and transmission shifting.
• Erratic speedometer readings
• Transmission shifting issues
• Cruise control not working
• Faulty vehicle speed sensor
• Damaged or corroded wiring/connectors
• Malfunctioning PCM
PCM: Powertrain Control Module
VSS: Vehicle Speed Sensor
• Use an OBD-II scanner to confirm the code.
• Inspect the vehicle speed sensor and its wiring for damage.
• Test the sensor's output with a multimeter.
• Replace the faulty vehicle speed sensor.
• Repair or replace damaged wiring/connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $300
Moderate
• Toyota Camry
• Ford F-150
• Honda Accord
• Regularly inspect and maintain vehicle sensors.
• Avoid driving through deep water which can damage sensors.
• Ensure electrical connections are clean and secure.
Sensor Issue
• Do not ignore the check engine light.
• Have the vehicle inspected by a professional.
• Avoid using cruise control until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on sensors.
P0503 has been a common code for vehicles with aging speed sensors or wiring issues.
Moderate – This issue can affect driving performance but is not immediately dangerous.
Ignoring this code may lead to inaccurate speed readings, affecting safe driving.
• Vehicle must be in motion.
• Check under various driving conditions.
The vehicle speed sensor is typically located on the transmission or differential.
Q: Can I drive with a P0503 code?
A: It's possible to drive, but it's not recommended as it can affect driving performance and safety.
Q: Will a P0503 code affect my fuel efficiency?
A: Yes, it can affect fuel efficiency as the vehicle may not shift gears optimally.
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