P0502
PowertrainSpeed Idlemoderate severityVehicle Speed Sensor A Low Input
What P0502 Means
Low or no signal from VSS.
Symptoms
- Speedometer reads zero
- No shifting
- Cruise control dead
Common Causes
- Faulty VSS
- Open circuit
- Disconnected sensor
Diagnostic Steps
- Test signal output
- Check wiring
- Test sensor
Where to start: Replace VSS or repair wiring.
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