Operation CHARM: Car repair manuals for everyone.

P0101




P0101 MAF SENSOR

DTC Logic


DTC DETECTION LOGIC

NOTE:
If DTC P0101 is displayed with other DTC, first perform the trouble diagnosis for other DTC.






DTC CONFIRMATION PROCEDURE


1. PRECONDITIONING

If DTC CONFIRMATION PROCEDURE has been previously conducted, always perform the following procedure before conducting the next test.
1.Turn ignition switch OFF and wait at least 10 seconds.
2.Turn ignition switch ON.
3.Turn ignition switch OFF and wait at least 10 seconds.
- GO TO 2.

2. PERFORM DTC CONFIRMATION PROCEDURE

1.Start engine and warm it up to normal operating temperature.
2.Drive the vehicle for at least 5 seconds under the following conditions:

CAUTION:
Always drive vehicle at safe speed.





NOTE:
- The gear must be fixed while driving the vehicle.
- Keep the accelerator pedal as steady as possible during cruising.
3.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Proceed to "Diagnosis Procedure" .
NO- INSPECTION END


Diagnosis Procedure


1. CHECK INTAKE SYSTEM

Check the following for connection.
- Air duct
- Vacuum hoses
- Intake air passage between air duct and intake manifold
Is the inspection result normal?
YES- GO TO 2.
NO- Reconnect the parts.

2. CHECK GROUND CONNECTION

1.Turn ignition switch OFF.
2.Check ground connection E15. Refer to Ground Inspection in "Circuit Inspection" Circuit Inspection.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace ground connection.

3. CHECK MASS AIR FLOW (MAF) SENSOR POWER SUPPLY CIRCUIT

1.Disconnect MAF sensor harness connector.
2.Turn ignition switch ON.
3.Check the voltage between MAF sensor harness connector and ground.





Is the inspection result normal?
YES- GO TO 5.
NO- GO TO 4.

4. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E55, F55
- Harness for open or short between mass air flow sensor and ECM
- Harness for open or short between mass air flow sensor and IPDM E/R
- Repair open circuit or short to ground or short to power in harness or connectors.

5. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.Turn ignition switch OFF.
2.Disconnect ECM harness connector.
3.Check the continuity between MAF sensor harness connector and ECM harness connector.





4.Also check harness for short to ground and short to power.
Is the inspection result normal?
YES- GO TO 6.
NO- Repair open circuit or short to ground or short to power in harness or connectors.

6. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.Check the continuity between MAF sensor harness connector and ECM harness connector.





2.Also check harness for short to ground and short to power.
Is the inspection result normal?
YES- GO TO 7.
NO- Repair open circuit or short to ground or short to power in harness or connectors.

7. CHECK INTAKE AIR TEMPERATURE SENSOR

Check the intake air temperature sensor. Refer to "Component Inspection" P0111.
Is the inspection result normal?
YES- GO TO 8.
NO- Replace MAF sensor (with intake air temperature sensor). Refer to "Removal and Installation" Removal And Installation.

8. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR

Check the EVAP control system pressure sensor. Refer to "Component Inspection" P0451.
Is the inspection result normal?
YES- GO TO 9.
NO- Replace EVAP control system pressure sensor. Refer to "Removal and Installation" Removal And Installation.

9. CHECK MAF SENSOR

Check the MAF sensor. Refer to "Component Inspection" .
Is the inspection result normal?
YES- Check intermittent incident. Refer to "Intermittent Incident" Intermittent Incident.
NO- Replace MAF sensor. Refer to "Removal and Installation" Removal And Installation.


Component Inspection


1. CHECK MASS AIR FLOW SENSOR-I

With CONSULT
1.Turn ignition switch OFF.
2.Reconnect all harness connectors disconnected.
3.Start engine and warm it up to normal operating temperature.
4.Connect CONSULT and select "DATA MONITOR" mode of "ENGINE".
5.Select "MAS A/F SE-B1" and check indication.





Without CONSULT
1.Turn ignition switch OFF.
2.Reconnect all harness connectors disconnected.
3.Start engine and warm it up to normal operating temperature.
4.Check the voltage between ECM harness connector and ground.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 2.

2. CHECK FOR THE CAUSE OF UNEVEN AIR FLOW THROUGH MASS AIR FLOW SENSOR

1.Turn ignition switch OFF.
2.Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
-Crushed air ducts
-Malfunctioning seal of air cleaner element
-Uneven dirt of air cleaner element
-Improper specification of intake air system parts
Is the inspection result normal?
YES- GO TO 4.
NO- GO TO 3.

3. CHECK MASS AIR FLOW SENSOR-II

With CONSULT
1.Repair or replace malfunctioning part.
2.Start engine and warm it up to normal operating temperature.
3.Connect CONSULT and select "DATA MONITOR" mode of "ENGINE".
4.Select "MAS A/F SE-B1" and check indication.





Without CONSULT
1.Repair or replace malfunctioning part.
2.Start engine and warm it up to normal operating temperature.
3.Check the voltage between ECM harness connector and ground.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 4.

4. CHECK MASS AIR FLOW SENSOR-III

With CONSULT
1.Turn ignition switch OFF.
2.Disconnect mass air flow sensor harness connector and reconnect it again.
3.Start engine and warm it up to normal operating temperature.
4.Connect CONSULT and select "DATA MONITOR" mode of "ENGINE".
5.Select "MAS A/F SE-B1" and check indication.





Without CONSULT
1.Turn ignition switch OFF.
2.Disconnect mass air flow sensor harness connector and reconnect it again.
3.Start engine and warm it up to normal operating temperature.
4.Check the voltage between ECM harness connector and ground.





Is the inspection result normal?
YES- INSPECTION END
NO- Clean or replace mass air flow sensor. Refer to "Removal and Installation" Removal And Installation.