DTC    P0102    Mass or Volume Air Flow Circuit Low Input

DTC    P0103    Mass or Volume Air Flow Circuit High Input

for Preparation Click here


DESCRIPTION

The Mass Air Flow (MAF) meter consists of a platinum hot wire, a temperature sensor and a control circuit installed in a plastic housing. The temperature sensor (located in the intake air by-pass of the housing) detect the intake air temperature.
There is little variation in the output from the mass air flow meter, as it is hardly affected by the resistance of the wire harness.
The internal circuit of the mass air flow meter contains a hot wire and cold wire. A voltage is output through a bridge circuit (refer to the illustration) indicating the cooling of the hot wire according to the intake air amount. This voltage is then converted into a periodic signal by the periodic signal conversion circuit and output to the ECM. The frequency varies between approximately 250 to 11000 Hz depending on the air flow rate. The ECM calculates the mass air flow rate based on this frequency.

A207644E01


P0102 
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Engine speed between 750 to 2500 rpm
Generated pulse period is 50 μsec. or less (MAF value is extremely high).
(1 trip detection logic)
  1. Open or short in Mass Air Flow (MAF) meter circuit
  2. Mass air flow meter
  3. ECM

P0103 
DTC Detection Drive Pattern
DTC Detection Condition
Trouble Area
Engine speed between 750 to 2500 rpm
Generated pulse period is 2100 μsec. or more (MAF value is extremely low).
(1 trip detection logic)
  1. Open or short in Mass Air Flow (MAF) meter circuit
  2. Mass air flow meter
  3. ECM

Related Data List 
DTC No.
Data List
P0102
MAF
P0103

HINT:
  1. If DTC P0102 is stored, the following symptoms may appear (as the ECU mistakenly determines that there is less air than the actual intake air amount, EGR is decreased to match the target EGR):
    1. Combustion noise worsens
  2. If DTC P0103 is stored, the following symptoms may appear (as the ECU mistakenly determines that there is more air than the actual intake air amount, EGR is increased to match the target EGR):
    1. Misfire
    2. White smoke
    3. Black smoke


WIRING DIAGRAM


A198994E03


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the ECM, the ECM needs Registration and Initialization (Click here).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT:
  1. When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the intelligent tester. Then after installing the new ECM, perform all of the initializations/registrations for the "Learning Values Write" function by following the instructions shown on the tester display.
  2. Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

1.INSPECT MASS AIR FLOW METER (POWER SOURCE CIRCUIT)


    A200308E01

  1. Disconnect the mass air flow meter connector.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A37-3 (+B) - Body ground
    		Ignition switch ON
    		11 to 14 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Mass Air Flow Meter)

  1. Reconnect the mass air flow meter connector.



NG
Go to step 3
OK


2.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM)

  1. Disconnect the mass air flow meter connector.



    A200282E01

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    A37-1 (VG) - A19-11 (VG)
    		Always
    		Below 1 Ω
    A37-2 (E2G) - A19-12 (EVG)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    A37-1 (VG) or A19-11 (VG) - Body ground
    		Always
    		10 kΩ or higher
    A37-2 (E2G) or A19-12 (EVG) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Mass Air Flow Meter)
    *2
    		Front view of wire harness connector
    (to ECM)

  1. Reconnect the mass air flow meter connector.

  1. Reconnect the ECM connector.



OK
Go to step 6

NG
Go to step 4

3.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - INTEGRATION RELAY)


    A200284E01

  1. Disconnect the mass air flow meter connector.

  1. Disconnect the integration relay connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    A37-3 (+B) - 1B-1
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    A37-3 (+B) or 1B-1 - Body ground
    		Always
    		10 Ω or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Mass Air Flow Meter)
    *2
    		Front view of wire harness connector
    (to Integration Relay)

  1. Reconnect the mass air flow meter connector.

  1. Reconnect the integration relay connector.



OK
Go to step 5

NG
Go to step 4

4.REPAIR OR REPLACE HARNESS OR CONNECTOR


NEXT
Go to step 9

5.CHECK ECM POWER SOURCE CIRCUIT

  1. Check ECM power source circuit (Click here).



NEXT
Go to step 9

6.REPLACE MASS AIR FLOW METER

  1. Replace the mass air flow meter (Click here).


NEXT


7.CHECK WHETHER DTC OUTPUT RECURS (DTC P0102 OR P0103)

  1. Connect the intelligent tester to the DLC3.

  1. Clear the DTCs (Click here).

  1. Start the engine and depress the accelerator pedal several times to the engine speed between 750 to 2500 rpm.

  1. Enter the following menus: Powertrain / Engine and ECT / DTC.

  1. Read the DTCs.
    Result 
    Result
    		Proceed to
    DTC P0102 or P0103
    		A
    No DTC output
    		B



B
END
A


8.REPLACE ECM

  1. Replace the ECM (Click here).


NEXT


9.CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED

  1. Connect the intelligent tester to the DLC3.

  1. Clear the DTCs (Click here).

  1. Start the engine and depress the accelerator pedal several times to the engine speed between 750 to 2500 rpm.

  1. Enter the following menus: Powertrain / Engine and ECT / DTC.

  1. Confirm that the DTC is not output again.


NEXT

END