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Home >> Eagle >> 1995 >> Summit DL >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes - OBD-II (2.4L) >> Diagnostic Tests >> Code P0505: Idle Control System Failure
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Code P0505: Idle Control System Failure

NOTE: For component terminal identification, see TERMINAL IDENTIFICATION  in this article. For wiring diagrams, see WIRING DIAGRAMS in the WIRING DIAGRAMS  section.
  1. Manufacturer does not provide component testing procedure without using scan tool. Ensure engine coolant temperature is 185-205°F (85-95°C). Place transmission in Park or Neutral. Turn off all accessories except A/C. Ensure A/C clutch is operating when A/C system is on. Allow engine to idle.
  2. Using scan tool, read Idle Air Control (IAC) position sensor step. See IAC POSITION SENSOR STEP SPECIFICATIONS  table. If scan tool does not read as specified, replace IAC position sensor. If readings are as specified, go to next step.
    IAC POSITION SENSOR STEP SPECIFICATIONS

    A/C Switch Position Standard Step Value
    Off 2-20
    On Increase From 8-50
    (1) Increase From 3-40
    (1) For A/T models. Brakes applied, transmission selector in "D" and A/C off.
  3. Disconnect PCM connector and IAC position sensor connector. Ground specified PCM connector terminal and using DVOM, check continuity between chassis ground and specified IAC connector terminal. See PCM-TO-IAC HARNESS CIRCUIT IDENTIFICATION  table. If continuity does not exist, repair wiring harness as necessary. If continuity exists, go to next step.
    PCM-TO-IAC HARNESS CIRCUIT IDENTIFICATION

    Application PCM Terminal No. IAC Terminal No.
    All Models 5 2
    18 4
    61 1
  4. With IAC position sensor connector disconnected, check continuity between chassis ground and IAC position sensor connector terminal No. 3. If continuity does not exist, repair wiring harness as necessary. If continuity exists, go to next step.
  5. With IAC position sensor connector disconnected and PCM connector connected, turn ignition switch to ON position. Check for voltage between chassis ground and IAC connector terminals No. 2 and No. 4. If voltage is not 4.8-5.2 volts on either circuit, replace PCM. If voltage is as specified, go to next step.
  6. Check voltage between chassis ground and IAC position sensor connector terminal No. 1. If voltage is not 4.8-5.2 volts, replace PCM. If voltage is as specified, condition required to set trouble code is not present at this time. Go to next step.
  7. Test is complete. Intermittent problem may exist. Road test vehicle (if necessary) and attempt to duplicate conditions that caused original complaint. Recheck for codes. If no codes are displayed, go to INTERMITTENT FAULTS .
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