Code result
P0502
Vehicle Speed Sensor Circuit Low Input
Moderate severity
What it means
The primary vehicle speed sensor (VSS A) reports a signal voltage below the plausible lower limit. With no usable speed signal the ECU loses cruise control, gear-shift logic and certain anti-stall functions.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Signal shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Sensor internal short
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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