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Electrical Load Signal - I30 & Q45: Q45

  1. Turn ignition off. Disconnect PCM harness connector. See Figure. Turn ignition on. Measure voltage between ground and PCM harness connector terminal No. 79. See Figure. Turn rear window defogger on. Battery voltage should exist. Turn rear window defogger off. Zero volts should exist. If voltage is as specified, go to next step. If voltage is not as specified, go to step  3.
  2. Measure voltage between ground and PCM harness connector terminal No. 72. Turn headlights on. Battery voltage should exist. Turn headlights off. Zero volts should exist. If voltage is as specified, test is complete. If voltage is not as specified, go to step  5.
  3. Check rear window defogger operation. If rear window defogger operates properly, go to next step. If rear window defogger does not operate properly, repair rear window defogger system. See REAR WINDOW DEFOGGERS article in ACCESSORIES & EQUIPMENT.
  4. Turn ignition off. Disconnect rear window defogger relay, located behind left kick panel. Check continuity of Blue/Red wire between rear window defogger relay harness connector terminal No. 5 and PCM harness connector terminal No. 79. If continuity exists, go to step  8. If continuity does not exist, repair open in Blue/Red wire.
  5. Check operation of headlights. If headlights operate properly, go to next step. If headlights do not operate properly, repair headlight system. See HEADLIGHT SYSTEMS article in ACCESSORIES & EQUIPMENT.
  6. Remove headlight relay, located in relay box on right side of engine compartment. Check continuity between PCM harness connector terminal No. 72 (Red/Yellow wire) and headlight relay harness connector terminal No. 6 (Blue/White wire). If continuity exists, go to next step. If continuity does not exist, repair open circuit.
  7. If vehicle is not equipped with xenon headlights, go to next step. If vehicle is equipped with xenon headlights, remove High Intensity Discharge (HID) relay, located next to headlight relay. Check continuity of Red/Yellow wire between PCM harness connector terminal No. 72 and HID relay harness connector terminal No. 7. If continuity exists, go to next step. If continuity does not exist, repair open in Red/Yellow wire.
  8. No problem is indicated at this time. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
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