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Power & Ground Circuits (I30 & Maxima)

  1. Start engine. If engine starts, go to step  5. If engine does not start, turn ignition off and on. Measure voltage between ground and ECM terminal No. 43 (Red wire) by backprobing. See Figure and Figure . If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See WIRING DIAGRAMS article.
  2. Turn ignition off. Disconnect ECM harness connector. Check continuity between ground and ECM harness connector terminals No. 48, 57, 106 and 108 (Black wires). Continuity should exist. Also, check circuits for short to voltage. Repair circuit(s) as necessary. If all circuits are okay, go to next step.
  3. Remove ECM relay. See Fig 1. Measure voltage between ground and ECM relay harness connector terminals No. 2 (White/Blue wire) and No. 6 (Purple wire). See Figure. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See WIRING DIAGRAMS article.
  4. Check continuity of White/Black wire between ECM relay harness connector terminal No. 1 and ECM harness connector terminal No. 26. Also, check circuit for short to ground and short to voltage. Repair circuit as necessary. If circuit is okay, go to next step.
  5. Turn ignition off. Measure voltage between ground and ECM terminal No. 67 (White/Blue wire) by backprobing. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See WIRING DIAGRAMS article.
  6. While turning ignition on and off, measure voltage between ground and ECM terminals No. 110 and 112 (Red/Green wires) by backprobing. Battery voltage should exist for a few seconds after turning ignition off, then drop to about zero volts. If voltage is as specified, go to step  10. If battery voltage does not exist, go to next step. If battery voltage exists for more than a few seconds, go to step  8.
  7. Remove ECM relay. See Fig 1. Measure voltage between ground and ECM relay harness connector terminal No. 3 (White/Blue wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit. See WIRING DIAGRAMS article.
  8. Remove ECM relay. Check continuity of Red/Green wire between ECM relay harness connector terminal No. 5 and ECM harness connector terminals No. 110 and 112. See Figure and Figure . Also, check circuit for short to ground and short to voltage. Repair circuit as necessary. If circuit is okay, go to next step.
  9. Check ECM relay. See RELAYS & SOLENOIDS . Replace, if necessary. If ECM relay is okay, go to next step.
  10. Turn ignition off. Disconnect ECM harness connector. Check continuity between ground and ECM harness connector terminals No. 48, 57, 106 and 108 (Black wires). Continuity should exist. Also, check circuits for short to voltage. Repair circuit(s) as necessary. If all circuits are okay, go to next step.
  11. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
Fig 1: Locating ECM Relay (I30 & Maxima)
G00051940Courtesy of NISSAN MOTOR CO., U.S.A.
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