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Home >> Kia >> 2003 >> Spectra Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1506 &/Or DTC P1508 >> Test Procedure
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Test Procedure

  1. Turn ignition off. Disconnect IAC valve 3-pin harness connector. See Figure . Turn ignition on. Measure voltage between ground and IAC valve harness connector terminal No. 3 (White/Green wire). Also, measure voltage between ground and IAC connector terminal No. 1 (White/Yellow wire). For both, voltage should be below 0.5V. If voltage is not as specified, Repair short to battery power in IAC opening and/or closing coil circuits as necessary and go to next step. If voltage is as specified, go to step  4 .
  2. Turn ignition off. Locate fuses and Main relay in engine compartment fuse/relay box. Check Main relay operation and fuses condition. For Main relay operation test. See FUEL PUMP & MAIN RELAYS (SPECTRA) under RELAYS & SOLENOIDS in SYSTEM & COMPONENTS TESTING article. Also if necessary check Main relay circuits. See ENGINE PERFORMANCE under SPECTRA in WIRING DIAGRAMS article. If fuses, relay and circuits are okay, go to next step. If fuses, relay or circuits are faulty, repair or replace as necessary, and go to step  4 .
  3. Turn ignition off. Measure resistance at IAC valve opening and closing coils (component side). See IDLE AIR CONTROL VALVE COIL RESISTANCE TEST  table. If resistances are as specified, thoroughly check IAC valve harness connector for loose, bent, corroded, contaminated, deteriorated or damaged connector terminals, repair or replace as necessary and go to next step. If any resistance is not as specified, temporarily install a known good IAC valve and check for proper operation. If problem is corrected, replace valve and go to next step.
    IDLE AIR CONTROL VALVE COIL RESISTANCE TEST

    IAC Valve Coils Measure Resistance Between IAC Valve Terminal No. Resistance Specifications
    Opening Coil 2 & 3 16.5-18.5 Ohms At 68°F (20°C)
    Closing Coil 1 & 2 14.5-16.5 Ohms At 68°F (20°C)
  4. After repair, return vehicle to original condition. Clear codes using Hi-Scan Pro/Kia Data Pro Scan tool or equivalent. Verify repairs by driving vehicle and monitoring for pending codes. If DTC is set during test drive, follow appropriate DTC test procedure.
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