[ Model - ECLIPSE CROSS / Year - 2018 ]
2018 / ECLIPSE CROSS / EC - Workshop Manual
13 -FUEL > 13A-DIRECT INJECTION AND MULTIPOINT FUEL INJECTION (DI AND MPI) > TROUBLESHOOTING > DIAGNOSIS CODE PROCEDURES > CODE NO. P0068 TRUSTFUL CHECK AIR FLOW SENSOR
Code No. P0068: Trustful Check Air Flow Sensor
 
 
 
 
FUNCTION
  • Compare the actual measurement of volumetric efficiency by an air flow sensor signal with volumetric efficiency estimated from a throttle position sensor (main and sub) signal.
 
 
TROUBLE JUDGEMENT
Check Conditions
  • Engine is running.
  • Throttle position sensors (main and sub) are normal.
Judgement Criterion
  • The difference between the volumetric efficiency (actual value) which is based on the air flow sensor value and that which is based on the throttle position sensor (main) exceeds a predetermined value.
or
  • The difference between the volumetric efficiency (actual value) which is based on the air flow sensor value and that which is based on the throttle position sensor (sub) exceeds a predetermined value.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • Estimate the throttle opening degree and the amount of intake air given by a normal sensor, and then carry out the fuel control.
  • Supercharging pressure is restricted.
 
 
PROBABLE CAUSES
  • Failed air flow sensor
  • Harness damage in air flow sensor circuit or loose connector contact
  • Failed intake air system
  • There is some foreign matter around air flow sensor
  • Failed supercharging pressure control system
  • Failed engine-ECU
 
 
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-IIISE diagnosis code
Is any other diagnosis code than P0068 set?
Inspection chart for diagnosis code (Refer to ).
Go to Step 2.
 
STEP 2. M.U.T.-IIISE data list
  • Data list reference table (Refer to ).
    1. Item 10: Air flow sensor
Is the check result normal?
Go to Step 3.
Check air flow sensor system. Check code No. P0102: air flow sensor circuit low input (Refer to ). Check code No. P0103: air flow sensor circuit high input (Refer to ).
 
STEP 3. Check air intake from intake hose and inlet manifold.
Is the check result normal?
Go to Step 4.
Repair.
 
STEP 4. Check air flow sensor.
  • Check that there is not foreign matter around air flow sensor.
Is the check result normal?
Go to Step 5.
Repair.
 
STEP 5. Check supercharging pressure.
  • Check supercharging pressure (Refer to GROUP 15 - On-vehicle Service - Supercharging Pressure Check ).
Is the check result normal?
Go to Step 6.
Repair.
 
STEP 6. M.U.T.-IIISE diagnosis code
  • Reconfirmation of diagnosis code.
Is the diagnosis code set?
Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).