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DTC P1320 - Ignition Signal

  1. Check Power Supply

    Turn ignition off. Disconnect ignition coil harness connectors. See Fig 1 and Fig 2 . Turn ignition on. Measure voltage as follows: See Fig 3.
    • On cylinder No. 1 and 2, between ground and ignition coil harness connector terminal No. 1.
    • On all except cylinder No. 1 and 2, between ground and ignition coil harness connector terminal No. 3.

    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. Verify harness continuity between ignition coil connector terminal No. 2 and ground. See Fig 4. 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 following ECM connector terminals and ignition coil connector terminals: See Fig 5.
    • Cylinders No. 1 and 2, ignition coil terminal No. "3" and ECM terminals No. 1, 2, 3, 7, 8, 9, 13 and 14.
    • All except cylinders No. 1 and 2, ignition coil terminal No. "1" and ECM terminals No. 1, 2, 3, 7, 8, 9, 13 and 14.

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

  4. Check Component

    Disconnect ignition coil. Check for continuity as follows: See Fig 6.
    • Cylinders No. 1 and 2, between ignition coil terminals No. "1" and "2".
    • All cylinders except No. 1 and 2, between ignition coil terminals No. "2" and "3".

    If continuity is present, ignition coil is okay. If continuity is not present, replace ignition coil.

Fig 1: Locating Left Bank Ignition Coils (Q45)
G96F10749Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Locating Right Bank Ignition Coils (Q45)
G96J10750Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 3: DTC 1320, Checking Power Supply Circuit (Q45)
G96A10751Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 4: DTC 1320, Checking Ground Circuit (Q45)
G96B10752Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 5: Checking Output Signal Circuit (Q45)
G96C10753Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 6: Checking Ignition Coil Resistance (Q45)
G96D10754Courtesy of NISSAN MOTOR CO., U.S.A.