P1505moderate severityPowertrain

IAC Valve Opening Coil Circuit Open

on 2016 Kia Optima 2.4L I4 · FWD

What this code means

The PCM has detected an open circuit in the IAC valve opening coil. The idle air control valve uses separate coils for opening and closing; the opening coil circuit is not completing the electrical path.

Symptoms

  • Check Engine Light
  • Low idle speed
  • Engine stalling at idle
  • Rough idle
  • Engine dies when coming to a stop

Common causes

  • Broken wire in IAC opening coil circuit
  • Corroded IAC connector
  • Faulty IAC valve with open coil winding
  • PCM connector issue
  • Poor ground connection

Diagnostic steps

  1. Test IAC valve opening coil resistance with multimeter
  2. Inspect IAC connector for corrosion or loose pins
  3. Check wiring continuity from PCM to IAC opening coil
  4. Test PCM output to IAC opening coil
  5. Check ground circuit

Repair notes

Replace the IAC valve if the opening coil is internally open; repair wiring or connector if the external circuit is at fault.

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