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Home >> Infiniti >> 1999 >> Q45 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing >> Fuel System >> Fuel Delivery >> Fuel Pump Control System (G20 & I30)
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Fuel Pump Control System (G20 & I30)

  1. Turn ignition on. Pinch fuel hose with fingers. For 5 seconds after ignition is turned on, pulsation should be felt on fuel hose. If pulsation is felt, system is okay. If pulsation is not felt, go to next step.
  2. Turn ignition off. Disconnect fuel pump relay harness connector. See Figure or Figure . Turn ignition on. Measure voltage between ground and fuel pump relay harness connector terminals No. 1 (Black/White wire on G20; Brown wire on I30) and No. 3 (Black/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See appropriate diagram in WIRING DIAGRAMS article.
  3. Turn ignition off. Disconnect fuel pump harness connector, located under rear seat. Check continuity between ground and fuel pump harness connector Black wire. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire.
  4. Check continuity of Black/Yellow wire between fuel pump harness connector and fuel pump relay harness connector terminal No. 5. If continuity exists, go to next step. If continuity does not exist, repair open in Black/Yellow wire.
  5. Disconnect PCM harness connector. See Figure or Figure . Check continuity of Black/Pink wire between fuel pump relay harness connector terminal No. 2 and PCM harness connector terminal No. 8 (on G20), or No. 117 (on I30). See Figure or Figure . If continuity exists, go to next step. If continuity does not exist, repair open in Black/Pink wire.
  6. Check fuel pump relay. See RELAYS & SOLENOIDS . Replace if necessary. If fuel pump relay is okay, check fuel pump. See FUEL PUMP . Replace if necessary. If fuel pump is okay, go to next step.
  7. 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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