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DTC P1320: Ignition Signal

  1. Check Power Supply  - Turn ignition off. Disconnect ignition coil harness connectors. See Figure and Figure . Turn ignition on. Measure voltage between ground and each ignition coil harness connector terminal No. 1. See Fig 1. If battery voltage is present, go to next step. If battery voltage is not present, repair harness or connectors as necessary.
  2. Check Ground Circuit  - Turn ignition off. Loosen and retighten engine ground bolts. See Figure. Verify harness continuity between each ignition coil connector terminal No. 2 (Black wire) and ground. If continuity is present, go to next step. If continuity is not present, repair harness or connectors as necessary.
  3. Check Output Signal Circuit  - Leave ignition off and ignition coils disconnected. Disconnect ECM harness connector. Verify harness continuity between each ignition coil connector terminal and the following ECM connector terminals:
    • Cylinder No. 1; ignition coil terminal No. 3 (Yellow/Red wire) and ECM terminal No. 1.
    • Cylinder No. 2; ignition coil terminal No. 3 (Red/Blue wire) and ECM terminal No. 14.
    • Cylinder No. 3; ignition coil terminal No. 3 (Gray wire) and ECM terminal No. 7.
    • Cylinder No. 4; ignition coil terminal No. 3 (White/Red wire) and ECM terminal No. 13.
    • Cylinder No. 5; ignition coil terminal No. 3 (Gray/Red wire) and ECM terminal No. 9.
    • Cylinder No. 6; ignition coil terminal No. 3 (Purple/White wire) and ECM terminal No. 8.
    • Cylinder No. 7; ignition coil terminal No. 3 (Blue/Red wire) and ECM terminal No. 3.
    • Cylinder No. 8; ignition coil terminal No. 3 (Green/Red wire) and ECM terminal No. 2.

    If continuity is not present, repair harness or connectors as necessary. If continuity is present at each check, go to next step.

  4. Check Ignition Coil  - Disconnect ignition coil harness connector. Using ohmmeter, check for continuity between ignition coil terminals No. 2 and 3. See Fig 2. If continuity is present, ignition coil is okay. If continuity is not present, replace ignition coil.
Fig 1: Locating Left Bank Ignition Coils
G97J06695Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Locating Right Bank Ignition Coils
G97B06696Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 3: Checking Power Supply Circuit
G97D06697Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 4: Checking Ignition Coil Resistance
G97F06698Courtesy of NISSAN MOTOR CO., U.S.A.