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Power & Ground Circuits (Frontier 2.4L & Xterra 2.4L)

NOTE: For engine performance related components locations, see Figure and Figure .
  1. Start engine. If engine starts, go to step  4. If engine does not start, go to next step.
  2. Turn ignition off, and then on. Backprobing at ECM, measure voltage between ground and ECM harness connector terminal No. 24 (White/Green wire). See Fig 1 and Fig 2 . If battery voltage exists, go to step  12. If battery voltage does not exist, go to next step.
  3. Check the following:
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors E43 and M65. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors M59 and F27.
    • Check for poor, loose, corroded or damaged terminal connections in fuse block junction connector E49.
    • Check fuse block fuses No. 13 (10-amp) and 27 (10-amp).
    • Check for open or short in circuits between ECM and fuse.
    If problem is found, repair as necessary. After repair, retest system.
  4. Turn ignition off. Backprobing at ECM, measure voltage between ground and ECM terminal No. 80 (Light Blue wire). If battery voltage exists, go to step  6. If battery voltage does not exist, go to next step.
  5. Check the following:
    • Check for poor, loose, corroded or damaged terminal connections at in-line harness connectors M81 and F36. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
    • Check for poor, loose, corroded or damaged terminal connections in fuse block harness connector M27.
    • Check fuse block fuses No. 13 (10-amp) and 27 (10-amp).
    • Check for open or short in circuits between ECM and fuses.
    If problem is found, repair as necessary. After repair, retest system.
  6. Turn ignition on, and then off. Backprobing at ECM, measure voltage between ECM terminals No. 67, 72 and 117 (Black/Pink wires). Battery voltage should exist at each terminal for a few seconds after ignition is turned off. If battery voltage exists for a few seconds, go to step  12. If battery voltage does not exist, go to next step. If battery voltage exists after a few seconds, go to step  11.
  7. Turn ignition off. Disconnect ECM 124-pin harness connector. ECM is located below instrument cluster. Remove lower instrument panel to access ECM. Disconnect ECM relay harness connector. ECM relay is mounted on bracket under instrument panel next to ECM. Check continuity in circuits between ECM harness connector terminals No. 67, 72 and 117 (all Black/Pink wires) and ECM relay harness connector terminal No. 3. See Fig 2 and Fig 3 . Continuity should exist. Also, check circuit for short to ground or short to voltage. If problem is found, repair as necessary. After repair, retest system. If no problem is found, leave harness connectors disconnected and go to next step.
  8. Measure volage between ground and ECM relay harness connector terminals No. 2 and then No. 5 (both wires are Light Blue). If battery voltage exists at both terminals, go to step  10. If battery voltage does not exist at both terminals, go to next step.
  9. Check for open or short in Light Blue wires between ECM relay and in-line harness connector F36. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. If problem is found, repair as necessary. After repair, retest system.
  10. Turn ignition off. Disconnect ECM 124-pin harness connector. ECM is located below instrument cluster. Remove lower instrument panel to access ECM. Check continuity in Orange/Black wire between ECM harness connector terminal No. 4 and ECM relay harness connector terminal No. 1. See Fig 2 and Fig 3 . Continuity should exist. Also, check circuit for short to ground or short to voltage. If problem is found, repair as necessary. After repair, retest system.
  11. Working with ECM relay, apply battery voltage and ground to terminals No. 1 and 2. See Fig 3. When battery voltage is applied, continuity should exist between terminals No. 3 and 5. When battery voltage is removed, continuity should not exist. Replace relay, if test values are not as specified.
  12. Turn ignition off. Disconnect ECM 124-pin harness connector. ECM is located below instrument cluster. Remove lower instrument panel to access ECM. Check continuity between ground and ECM harness connector terminals No. 10, 19, 116 and 124 (Black/Red wire), and No. 25 and 32 (Black/Yellow wire). See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Continuity should exist. Also, check circuits for short to voltage. If no problem is found, go to next step. If problem is found, repair as necessary. After repair, retest system.
  13. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
Fig 1: Locating Engine Control Module & Engine Control Module Harness Connector (Frontier & Xterra)
G98J01320Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Identifying Engine Control Module Harness Connector Terminals (Frontier & Xterra)
G96H10790Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 3: Identifying 4-Pin ECM Or Fuel Pump Relay Terminals (Frontier & Xterra)
G97F06716Courtesy of NISSAN MOTOR CO., U.S.A.
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