987 · Exhaust

P0413

Secondary Air Injection System Switching Valve "A" Circuit Open

LOW SEVERITY

Open circuit on the secondary air injection switching valve.

SYMPTOMS

  • Check-engine light
  • Drivability or performance issues

LIKELY CAUSES

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

DIAGNOSIS STEPS

  • Inspect the secondary air switching 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

  • Secondary air valve
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