CIRCUIT OPERATION
- Power is supplied by the ECM connector terminal number 76 to the mass airflow sensor connector terminal number 1.
- The mass airflow sensor connector terminal number 3 is ground through the ECM connector terminal number 98.
- The sensor signal is inputted to the ECM connector terminal number 78 from the mass airflow sensor connector terminal number 2.
TECHNICAL DESCRIPTION
The mass airflow sensor monitors the state inside the mass airflow sensor.
DESCRIPTIONS OF MONITOR METHODS
There is an abnormality within the mass airflow sensor, it sends a malfunction signal to the ECM.
MONITOR EXECUTION
Continuous.
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
Sensor (The sensor below is determined to be normal)
DTC SET CONDITIONS
Check Conditions
- More than 3 seconds have passed since the power supply mode of the electric motor switch was ON.
- While engine is running.
- 12V battery positive voltage is more than 10.0 volts and is less than 16.5 volts.
Judgment Criterion
- When failure signal of mass airflow sensor is a sensor failure (1h, 2h, 3h, 6h) for 2 seconds.
FAIL-SAFE AND BACKUP FUNCTION
Carry out the fuel control by estimating the amount of intake air from throttle opening degree and a normal sensor.
OBD-II DRIVE CYCLE PATTERN
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Mass airflow sensor failed.
- ECM failed.