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Fuel Injector Circuits (Pathfinder)

  1. Start engine. If engine does not start, go to step  5. If engine starts, listen to each injector. If every injector clicks, system is okay. If any injector does not click, go to next step.
  2. Turn ignition off. Disconnect inoperative injector harness connector. Turn ignition on. Measure voltage between ground and injector harness connector White/Red wire. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See appropriate wiring diagram in WIRING DIAGRAMS article.
  3. Turn ignition off. Disconnect PCM harness connector. Check continuity of specified wire between PCM harness connector and appropriate injector harness connector. See FUEL INJECTOR CIRCUIT IDENTIFICATION (PATHFINDER)  table. See Figure. If continuity exists, go to next step. If continuity does not exist, repair open in appropriate wire.
  4. Check fuel injector. See FUEL INJECTOR . Replace, if necessary. If injector is okay, no problem is indicated at this time. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
  5. Turn ignition off. Disconnect Black 8-pin injector sub-harness connector located near oil filler cap. Turn ignition on. Measure voltage between ground and injector sub-harness connector terminal No. 1 (White/Red wire). See Figure. If battery voltage exists, reconnect injector sub-harness connector and go to step  2. If battery voltage does not exist, go to next step.
  6. Turn ignition off. Remover ECCS relay from underhood relay box. Measure voltage between ground and ECCS relay harness connector terminals No. 1 (White/Red wire) and No. 5 (Red/White wire). See Figure. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See appropriate wiring diagram in WIRING DIAGRAMS article.
  7. Check continuity of White/Red wire between ECCS relay harness connector terminal No. 3 and injector sub-harness connector terminal No. 1. See Figure and Figure . If continuity exists, go to next step. If continuity does not exist, repair open in White/Red wire.
  8. Disconnect PCM harness connector. See Figure. Check continuity of Blue/Black wire between ECCS relay harness connector terminal No. 2 and PCM harness connector terminal No. 4. See Figure and Figure . If continuity exists, go to next step. If continuity does not exist, repair open in Blue/Black wire.
  9. Check ECCS relay. See RELAYS  under RELAYS & SOLENOIDS. Replace, if necessary. If ECCS relay is okay, check PCM power supply. See POWERTRAIN CONTROL MODULE (PCM)  under COMPUTERIZED ENGINE CONTROLS.
FUEL INJECTOR CIRCUIT IDENTIFICATION (PATHFINDER)

Injector No. PCM Terminal No. (1) Wire Color
1 102 White
2 109 Yellow
3 104 Yellow/Red
4 111 White/Blue
5 106 White/Green
6 113 White/Black
(1) See Figure.
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