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DTC P0100: Mass Airflow (MAF) Sensor: Procedure

  1. If malfunction "A" or "C" was duplicated, go to next step. If malfunction "B" or "D" was duplicated, check air intake system and vacuum hoses for leaks. Repair as necessary and retest system. If no leaks are found, go to next step.
  2. Turn ignition off. Loosen and retighten 2 engine ground bolts. See Fig 1. Disconnect MAF sensor harness connector located on air intake duct near air cleaner housing. Turn ignition on. Measure voltage between ground and MAF sensor harness connector terminal No. 3 (Red/Green wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit and retest system. See WIRING DIAGRAMS article.
  3. Turn ignition off. Disconnect ECM harness connector. See Figure. Check continuity of Black wire between ECM harness connector terminal No. 62 and MAF sensor harness connector terminal No. 2. See Figure. Also, check circuit for short to ground and short to voltage. Repair circuit as necessary and retest system. If circuit is okay, go to next step.
  4. Check continuity of White wire between ECM harness connector terminal No. 65 and MAF sensor harness connector terminal No. 1. Also, check circuit for short to ground and short to voltage. Repair circuit as necessary and retest system. If circuit is okay, go to next step.
    5. CAUTION: DO NOT use ECM ground terminals when measuring voltage.
  5. Reconnect all harness connectors. Start engine and warm to normal operating temperature. Measure voltage between ground and ECM terminal No. 65 by backprobing, with engine at specified speeds. See MAF SENSOR VOLTAGE  table. If voltage is as specified, go to step  7. If voltage is not as specified, go to next step.
  6. Disconnect and reconnect MAF sensor harness connector and repeat test. If voltage is still not as specified, remove MAF sensor and check hot film for damage or dust. Repair or replace MAF sensor, if necessary and retest system. If voltage is now as specified, go to next step.
  7. No problem is indicated at this time. Problem may be intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article.
MAF SENSOR VOLTAGE

Condition Volts
Key On, Engine Off Less Than 1.0
Engine Idling 1.0-1.7
2500 RPM About 2.1
Idle To 4000 RPM (1) 1.0-1.7 To About 4.0
(1) Voltage should increase in proportion to engine speed.
Fig 1: Locating Engine Ground Bolts
G97A06587Courtesy of NISSAN MOTOR CO., U.S.A.
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