DTC 12: Mass Airflow (MAF) Sensor

Check Power Supply - Turn ignition off and disconnect MAF sensor harness connector. Turn ignition on. Measure voltage between MAF sensor harness connector terminal "b" (Orange wire) and ground. See Fig 1 and Fig 2 . If battery voltage is present, go to next step. If battery voltage is not present, verify harness continuity between MAF sensor and ECM, and MAF sensor and ECCS relay. Repair harness or connectors as necessary.

Fig 1: Locating MAF Sensor Harness Connector
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 2: DTC 12, Checking Power Supply
Courtesy of NISSAN MOTOR CO., U.S.A.
Check Ground Circuit - Turn ignition off and disconnect ECM harness connector. Check continuity between MAF sensor connector terminal "c" (White wire) and ECM terminal No. 17. See Figure , Figure and Fig 3 . If continuity is present, go to next step. If continuity is not present, repair harness or connectors as necessary.
Check Input Signal Circuit - Check continuity between MAF sensor connector terminal "d" (Orange wire) and ECM harness connector terminal No. 16. See Fig 4 . If continuity is not present, repair harness or connectors as necessary.
Check Component - Inspect MAF sensor. See I - SYS/COMP TESTS article in the ENGINE PERFORMANCE Section. Replace MAF sensor if necessary and perform FINAL CHECK .

Fig 3: DTC 12, Checking Ground Circuit

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

Fig 4: DTC 12, Checking Input Signal Circuit

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