6) Check Output Signal Circuit

Turn ignition off. Disconnect ECM harness connector. Verify harness continuity between ECM harness connector terminals and ECM side of EFI Gray connector terminals as follows:

• ECM terminal No. 101 and EFI terminal "s" (Yellow wire).
• ECM terminal No. 103 and EFI terminal "u" (White wire).
• ECM terminal No. 105 and EFI terminal "w" (Red/Blue wire).
• ECM terminal No. 110 and EFI terminal "t" (Light Green/Black wire).
• ECM terminal No. 112 and EFI terminal "v" (Pink/Black wire).
• ECM terminal No. 114 and EFI terminal "x" (Gray wire).

See Fig 1 . If continuity is not present, repair harness or connectors as necessary. If continuity is present, inspect ECM pin terminals for damage or check for bad connection of ECM harness connector. Perform FINAL CHECK.

Fig 1: DTC 51, Checking Output Signal Circuit Continuity

Courtesy of NISSAN MOTOR CO., U.S.A.