DTC P0100 Mass or Volume Air Flow Circuit |
DTC P0102 Mass or Volume Air Flow Circuit Low Input |
DTC P0103 Mass or Volume Air Flow Circuit High Input |
DESCRIPTION
The Mass Air Flow (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 the 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 given temperature. The flow of incoming air cools both the wire and an internal thermistor, affecting their resistance. To maintain a constant current value, the ECM varies the voltage applied to these components in the MAF meter. The voltage level is proportional to the airflow through the sensor, and the ECM uses it to calculate the intake air volume.
The circuit is constructed so that the platinum hot wire and the temperature sensor create a bridge circuit, and the power transistor is controlled so that the potentials of A and B remain equal to maintain the predetermined temperature.
- HINT:
- When any of these DTCs are stored, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is calculated by the ECM, according to the engine RPM and throttle valve position. Fail-safe mode continues until a pass condition is detected.
DTC No. | DTC Detection Condition | Trouble Area |
P0100 | MAF meter voltage less than 0.2 V, or more than 4.9 V, for 3 seconds (1 trip detection logic: Engine speed less than 4000 rpm) (2 trip detection logic: Engine speed more than 4000 rpm or more) |
|
P0102 | MAF meter voltage less than 0.2 V for 3 seconds (1 trip detection logic: Engine speed less than 4000 rpm) (2 trip detection logic: Engine speed 4000 rpm or more) |
|
P0103 | MAF meter voltage more than 4.9 V for 3 seconds (1 trip detection logic: Engine speed less than 4000 rpm) (2 trip detection logic: Engine speed 4000 rpm or more) |
|
- HINT:
- When any of these DTCs are stored, check the air-flow rate by entering the following menus on a Techstream: Powertrain / Engine and ECT / Data List / MAF.
Mass Air Flow Rate (gm/sec) | Malfunction |
Approximately 0.0 |
|
160.0 or more |
|
WIRING DIAGRAM
INSPECTION PROCEDURE
- NOTICE:
- Inspect the fuses for circuits related to this system before performing the following inspection procedure.
- HINT:
- Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
1.READ VALUE USING TECHSTREAM (MAF) |
Connect the Techstream to the DLC3.
Start the engine.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.
Read the values displayed on the Techstream.
*: The value must change when the throttle valve is opened or closed with the engine runningResult MAF (gm/sec) Proceed to 0.0 A 160.0 or more B Between 1.0 and 160.0* C
|
| ||||
|
| ||||
A | |
2.CHECK TERMINAL VOLTAGE (POWER SOURCE OF MASS AIR FLOW METER) |
Disconnect the mass air flow meter connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection Switch Condition Specified Condition C26-1 (+B) - Body ground Ignition switch ON 11 to 14 V
Text in Illustration *a Front view of wire harness connector
(to Mass Air Flow Meter)
Reconnect the mass air flow meter connector.
|
| ||||
OK | |
3.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) |
Disconnect the C26 mass air flow meter connector.
Disconnect the C20 ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition C26-3 (VG) - C20-118 (VG) Always Below 1 Ω C26-2 (E2G) - C20-116 (E2G)
- Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition C26-3 (VG) or C20-118 (VG) - Body ground Always 10 kΩ or higher
Reconnect the mass air flow meter connector.
Reconnect the ECM connector.
|
| ||||
OK | |
4.INSPECT MASS AIR FLOW METER |
Perform On-vehicle Inspection (Click here).
Perform Inspection.
Remove the mass air flow meter (Click here).
Check for foreign matter in the air flow passage of the mass air flow meter.
- OK:
- There is no foreign matter.
Inspect the function of the mass air flow meter.
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / MAF.
Start the engine.
Check that the mass air flow meter value changes when the engine is raced.
- OK:
- The reading changes.
|
| ||||
OK | ||
|
5.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - EFI RELAY) |
Disconnect the C26 mass air flow meter connector.
Remove the integration relay from the engine room relay block.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition C26-1 (+B) - 1A-4 Always Below 1 Ω
- Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition C26-1 (+B) or 1A-4 - Body ground Always 10 kΩ or higher
Reinstall the integration relay.
Reconnect the mass air flow meter connector.
|
| ||||
OK | ||
|
6.CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER - ECM) |
Disconnect the C26 mass air flow meter connector.
Disconnect the C20 ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition C26-3 (VG) - C20-118 (VG) Always Below 1 Ω C26-2 (E2G) - C20-116 (E2G)
- Standard Resistance (Check for Short):
Tester Connection Condition Specified Condition C26-3 (VG) or C20-118 (VG) - Body ground Always 10 kΩ or higher
Reconnect the mass air flow meter connector.
Reconnect the ECM connector.
|
| ||||
OK | |
7.CHECK HARNESS AND CONNECTOR (SENSOR GROUND) |
Disconnect the C26 mass air flow meter connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance (Check for Open):
Tester Connection Condition Specified Condition C26-2 (E2G) - Body ground Always Below 1 Ω
Reconnect the mass air flow meter connector.
|
| ||||
OK | ||
|