ECD SYSTEM, Diagnostic DTC:P0101

DTC Code DTC Name
P0101 Mass Air Flow Circuit Range / Performance Problem

DESCRIPTION

The Mass Air Flow (MAF) meter uses a platinum hot wire. The hot wire MAF meter consists of a platinum hot wire, thermistor and a control circuit installed in a plastic housing. The hot wire MAF meter works on the principle that the hot wire and thermistor located in the intake air bypass of the housing detect any changes in the IAT.

The hot wire is maintained at the set temperature by controlling current flow through the hot wire. This current flow is then measured as the output voltage of the MAF meter.

The circuit is constructed so that the platinum hot wire and thermistor provide a bridge circuit with the power transistor controlled so that the potential of A and B remains equal to maintain the set temperature.

A01CI1AE01
DTC No. DTC Detection Condition Trouble Area
P0101

Air flow rate from mass air flow meter is out of specified threshold under the following conditions (2 trip detection logic):


  • Engine speed is idling or more than 2000 rpm

  • Engine coolant temperature is 70°C (158°F) or higher

 Mass air flow meter

INSPECTION PROCEDURE

Tech Tips

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.

PROCEDURE


  1. CHECK OTHER DTC OUTPUT


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to the ON position.

    3. Turn the tester on.

    4. Enter the following menu items: Powertrain / Engine and ECT / Data List / DTC.

    5. Read the DTCs.

      Result
      Display (DTC output) Proceed to
      P0101 A
      P0101 and other DTCs B

    B

    GO TO DTC CHART

    A

    REPLACE MASS AIR FLOW METER