P0502 – OBD-II DTC

OBD-II DTC P0502 – Vehicle Speed Sensor Range/Performance

DTC P0502 meaning

DTC P0502 refers to a diagnostic trouble code that indicates a problem with the vehicle speed sensor (VSS) range or performance. The vehicle speed sensor is responsible for monitoring the speed of the vehicle and sending this information to the engine control module (ECM) or powertrain control module (PCM). When the signal from the VSS is outside the expected range, this code is triggered, indicating a potential issue with the sensor or its circuit.

DTC P0502 symptoms

Common symptoms associated with DTC P0502 may include:

• Inaccurate speedometer readings
• Erratic or fluctuating speedometer behavior
• Transmission shifting issues
• Check Engine Light illuminated
• Reduced fuel efficiency

DTC P0502 causes

Several factors can lead to the triggering of DTC P0502, including:

• Faulty vehicle speed sensor
• Damaged or corroded wiring or connectors in the VSS circuit
• Faulty ECM or PCM
• Issues with the vehicle’s transmission
• Mechanical problems affecting the speed sensor, such as a damaged gear

DTC P0502 seriousness

DTC P0502 can be considered a moderate to serious issue. While it may not cause immediate vehicle failure, it can lead to inaccurate speed readings, which can affect driving safety and vehicle performance. Additionally, it may cause transmission problems if not addressed, leading to more significant repairs down the line.

How to diagnose DTC P0502

To diagnose DTC P0502, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the P0502 code.
2. Check for any additional trouble codes that may provide more context.
3. Inspect the vehicle speed sensor and its wiring for any visible damage or corrosion.
4. Test the voltage and resistance of the VSS using a multimeter.
5. Check the ECM or PCM for proper operation and any related codes.
6. Perform a road test to monitor the speed sensor’s performance while observing the speedometer and transmission behavior.

How to fix DTC P0502 step-by-step instructions

To fix DTC P0502, follow these steps:

1. Inspect the vehicle speed sensor for any physical damage or wear.
2. Check the wiring and connectors for corrosion, breaks, or loose connections.
3. If the sensor is faulty, replace it with a new one.
4. Repair any damaged wiring or connectors as needed.
5. Clear the DTC using an OBD-II scanner.
6. Perform a road test to ensure the issue is resolved and the code does not return.

How to erase DTC P0502

To erase DTC P0502, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn the ignition key to the “On” position without starting the engine.
3. Access the scanner’s menu and select the option to clear or erase trouble codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to ensure the code does not reappear.