What is the P0502 fault description? What is the description of the Vehicle Speed Sensor A low Input fault? How do I fix the P0502 fault code What are the causes and symptoms of the P0502 error code?
What is the P0502 Fault code? What does it signify?
A P0502 code is generated when the powertrain controller module (PCM), detects conflicting speed readings between the vehiclespeed sensor (VSS), and the wheels speed sensors. The code’s description includes the “A” symbol, which refers to the primary VSS for vehicles equipped with more than one speed sensor.
Many vehicle systems rely on the data from the speed sensors. The speed sensor data is used by the PCM, various control modules, and many other systems to control vehicle performance, engine efficiency, and cruise control, stability, and traction control systems.
VSS sensor uses an electromagnetic sensor and a rotating relay wheel. It can be mounted on either the transmission body or the drivetrain, such as the rear differential. The reluctor wheel is usually connected to the output shaft of the gearbox and rotates with it. The impeller’s rotation creates a magnetic field between the gears that changes the voltage. These voltage fluctuations allow the PCM monitor the vehicle’s speed.
The PCM monitors vehicle speeds using input data from one of several vehicle speed sensors. It compares VSS data with ABS speed sensors and the electronic brake system controller module to determine transmission shift point, regulate and control safety devices. If the data from both the primary and secondary speed sensors are not compatible, malfunction code P0502 will be set. This is when the voltage signal from the primary speedsensor is lower than what the PCM anticipates. A mechanical or electrical fault could cause the low voltage.
There are many vehicles that fall prey to the P0502 fault code, including, but not limited, to models of Chevrolet and Cadillac, Saabs, Peugeot, Volkswagens, Opels, Saturns, Isuzus, Subarus, GMCs, and Volvo.
What causes the P0502 Fault code?
VSS sensors may have different settings. VSS may have different reasons. These are the most common reasons that P0502 is triggered
- – Defective primary or wheel speed sensors
- – Sensor wires and connectors can be short circuited, worn or broken.
- Poor electrical connections
- – A damaged speed sensor reluctor wheel
- – Replace damaged wheel speed sensor relay wheels
- Extremely dirty speed sensors
- Wrong size tires
- – Issues with the PCM and other modules
What are the symptoms for P0502 Malfunction Code
You may experience the following symptoms if your vehicle has the code P0502.
- – Illumination for the check engine light
- Depending on whether the VSS signals output is too low, too high, or too high, gear changes can be made too quickly or late.
- – The speedometer won’t work properly compared to the vehicle speed
- The gearbox’s uneven gear shifting will result in a reduction in engine performance.
- – Your vehicle’s ABS or traction control system may not be working properly. These systems’ fault lights may be displayed on the instrument panel.
- Other fault codes can be adjusted for ABS and gearbox systems
How to Fix the P0502 Fault Code
These are some of the possible repairs that could resolve the P0502 fault codes:
- – Replacing speed sensor
- – Repair or replacement wires and connectors in speed sensor circuit
- – Replacing one, or more, wheel speed sensors
- – Reluctor rings can be replaced or checked.
- – Cleaning all speed sensor
- – Checking wheel dimensions and changing them if they’re wrong.
- – Reprogramming the PCM or replacing it
How Serious Is the P0502 Fault Code
If the code is P0502, it means that the VSS has stopped working. Driving with this code for too long can result in erratic gear changes or transmission damage. Additionally, safety systems such ABS and the Traction Control System may be disabled. You should drive the vehicle with extreme caution, especially in adverse weather conditions.
