P0502: Vehicle Speed Sensor Low Input
Can you still drive? You can drive short distances, but the transmission may not shift properly and your speedometer will be inaccurate. Get it repaired soon.
What Does P0502 Mean?
Code P0502 indicates that the PCM is receiving a lower-than-expected signal from the vehicle speed sensor. This typically means the sensor is producing no output or its voltage has dropped below the acceptable threshold. The issue often points to an electrical fault rather than a mechanical one.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonCommon Causes
- Failed vehicle speed sensor
- Open or shorted wiring to VSS
- Poor ground connection at sensor
- Faulty PCM input circuit
- Corroded connector pins
Symptoms
- Speedometer reads zero while driving
- Check engine light on
- Transmission stuck in one gear
- Cruise control will not engage
Diagnostic Steps
- 1Check for related codes such as P0500, P0501, or P0503
- 2Inspect VSS connector and wiring for opens or shorts
- 3Measure VSS reference voltage at the connector with key on
- 4Test VSS resistance with a multimeter
- 5Verify ground circuit integrity at the sensor
Recommended Parts & Tools
vehicle speed sensor
electrical connector cleaner
Estimated Repair Cost
| Type | Estimated Cost |
|---|---|
| Total Repair Cost Range | $60 - $350 |
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Chat with AI About P0502Commonly Affected Vehicles
Related Recalls
Frequently Asked Questions
What is the difference between P0501 and P0502?
P0501 indicates an erratic or out-of-range signal, while P0502 specifically indicates a low or absent signal from the vehicle speed sensor.
Is the vehicle speed sensor easy to replace?
On most vehicles the VSS is accessible on the transmission or transfer case, making it a relatively straightforward replacement for a DIY mechanic.
Community Fix Reports
Community reports are user-submitted and not verified by Auto AI Buddy. Results may vary.
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