DTC P0101 Mass or Volume Air Flow Circuit Range / Performance Problem
DESCRIPTION
Refer to DTC P0100
DTC No. |
DTC Detection Condition |
Trouble Area |
P0101 |
|
MAF meter |
MONITOR DESCRIPTION
The MAF meter is a sensor that measures the amount of air flowing through the throttle valve. The ECM uses this information to determine the fuel injection time and to provide an appropriate air-fuel ratio.
Inside the MAF meter, there is a heated platinum wire which is exposed to the flow of intake air. By applying a specific electrical current to the wire, the ECM heats it to a specific temperature. The flow of incoming air cools both the wire and an internal thermistor, changing their resistance. To maintain a constant current value, the ECM varies the voltage applied to these components of the MAF meter. The voltage level is proportional to the air flow through the sensor, and the ECM uses it to calculate the intake air volume.
If there is a defect in the sensor, or an open or short in the circuit, the voltage level deviates from the normal operating range. The ECM interprets this deviation as a malfunction in the MAF meter and sets the DTC.
Example: If the voltage is more than 2.2 V, or less than 0.73 V while idling, the ECM determines that there is a malfunction in the MAF meter and sets the DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
WIRING DIAGRAM
Refer to DTC P0100
INSPECTION PROCEDURE
HINT: Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction
1 CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0101)
Result
HINT: If any DTCs other than P0101 are output, troubleshoot those DTCs first.
GO TO DTC CHART
Mute Signal Circuit between Radio and Navigation Assembly and
Stereo Component Amplifier
DESCRIPTION
This circuit sends a signal to the stereo component amplifier to mute noise.
Because of that, the noise
produced by changing the sound source ceases.
If there is an open in the circuit, noise can be heard from the speakers when
changing the sound source.
If there is a short i ...
When servicing full-time 4wd vehicles
The full-time 4WD SIENNA is equipped with the open
center differential system.
If incorrect preparations or test procedures are used, the
test will not only be unsuccessful, but may be dangerous
as well.
Therefore, before beginning any such servicing or test,
be sure to check the following ...
Throttle / Pedal Position Sensor / Switch "A"
HINT:
These DTCs relate to the Throttle Position (TP) sensor.
DESCRIPTION
HINT:
This ETC (Electrical Throttle Control System) does not use a throttle cable.
The Throttle Position (TP) sensor is mounted on the throttle body, and detects
the opening angle of the
throttle valve. This sens ...