987 · Fuel

P0459

EVAP System Purge Control Valve Circuit High

LOW SEVERITY

EVAP purge control valve circuit voltage high.

SYMPTOMS

  • Check-engine light
  • Drivability or performance issues

LIKELY CAUSES

  • Faulty EVAP purge valve
  • Open circuit or short to power in the signal wire
  • Corroded or disconnected connector
  • ECM/PCM fault (rare)

DIAGNOSIS STEPS

  • Inspect the EVAP purge valve wiring and connector
  • Check the signal circuit for an open or short to power
  • Verify reference voltage and ground
  • Compare live data to expected
  • Replace the component if confirmed faulty

RELATED PARTS

  • Purge valve
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