P0502 - Vehicle Speed Sensor Low Input

Vehicle speed sensor signal is too low or missing.

Treat the code as the starting point: compare symptoms, likely causes, and repair paths before pricing parts or moving into an estimate.

Code Overview

Vehicle speed sensor signal is too low or missing.

Common Causes

• Failed speed sensor
• Short to ground
• Tone ring damage
• Wiring issue

Diagnostic Steps

1. Watch speed PID during a road test
2. Inspect the sensor and tone ring area
3. Check the signal circuit for damage

Likely Repairs & Cost Guides

Use symptoms, scan data, and quick checks to confirm the likely repair path before pricing parts. The estimator helps compare repair paths before replacing anything unnecessarily.

Related OBD Codes

Browse nearby code-family pages when the same fault pattern overlaps across systems, such as misfire, lean fuel trim, EVAP sealing, cooling, or charging faults.

Next Steps

Move from code lookup to diagnosis, then estimate the likely repair only after symptoms, causes, and checks point to the same path.