Mass Airflow Sensor
Faults in mass airflow sensor circuit may set Code 12. To test system, see CODE 12 diagnostic procedures in TESTS W/CODES
article.
- To test airflow sensor, warm engine to operating temperature. Pull rubber protector away from mass airflow sensor connector so terminals can be backprobed. At mass airflow sensor connector, measure voltage at Orange wire (Altima, NX and Sentra), or White/Blue (Quest), or White wire (all others).
- If voltage is not as specified in MASS AIRFLOW SENSOR VOLTAGE TEST
table, check for dust or foreign material in hot wire air passage of mass airflow sensor. If air passage is okay, replace mass airflow sensor.
NOTE:
On 300ZX, measure voltage at White wire terminal closest to Orange wire terminal; other White wire is for power supply.
MASS AIRFLOW SENSOR VOLTAGE TEST
| Application |
Volts With KOEO |
Volts At Idle |
| Altima |
0.2 |
0.85-1.35 |
| Maxima |
| VG30E Engine |
Less Than 0.5 |
1.0-1.3 |
| VE30DE Engine |
Less Than 1.0 |
0.8-1.5 |
| NX & Sentra |
| 1.6L |
Less Than 1.0 |
0.7-1.1 |
| 2.0L |
Less Than 1.0 |
1.3-1.7 |
| Pathfinder |
Less Than 1.0 |
1.5-2.0 |
| Pickup |
| 2.4L |
|
|
| 3.0L |
Less Than 1.0 |
1.5-2.0 |
| Quest |
0.5 |
1.0-1.7 |
| 240SX |
0.2 |
1.0-1.4 |
| 300ZX |
0.8 |
0.8-1.5 |