Code No. P0108: Manifold Absolute Pressure Sensor Circuit High Input




OPERATION



  • A power voltage of 5 V is applied to the manifold absolute pressure sensor power terminal from the engine-ECU connector terminal MAP5 and earthed to the engine-ECU connector terminal MAPE from the manifold absolute pressure sensor connector terminal.
  • The sensor signal is inputted to the engine-ECU connector terminal MAP from the manifold absolute pressure sensor output terminal.

FUNCTION



  • The manifold absolute pressure sensor detects a change in inlet manifold pressure and inputs the signal to the engine-ECU.
  • In response to the signal, the engine-ECU corrects the fuel injection amount, etc.

TROUBLE JUDGMENT


Check Conditions
  • Engine coolant temperature is more than 0°C at the engine starts.
  • Volumetric efficiency is more than 20 %.


  • More than 8 minutes have passed since the engine starting sequence was completed, when the engine coolant temperature at engine start is less than 0°C.
  • Volumetric efficiency is more than 20 %.
Judgement Criterion
  • Manifold absolute pressure sensor output voltage is more than 4.6 V (corresponding to a manifold absolute pressure of 117 kPa or more) for 2 seconds.

FAIL-SAFE AND BACKUP FUNCTION



  • Control as if the inlet manifold vacuum pressure is 101 kPa.

PROBABLE CAUSES



  • Failed manifold absolute pressure sensor
  • Open circuit or harness damage in manifold absolute pressure sensor circuit or loose connector contact

  • Failed engine-ECU

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III data list



  • Data list reference table (Refer to ).

  1. Item 8: Manifold absolute pressure sensor

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Go to Step 2.

STEP 2. Perform resistance measurement at manifold absolute pressure sensor connector.



  • Disconnect connector, and measure at harness side.
  • Resistance between terminal engine-ECU MAPE line and body earth.
OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 5.
Go to Step 3.

STEP 3. Check harness between manifold absolute pressure sensor connector terminal and engine-ECU connector terminal MAPE.



  • Check earthing line for open circuit and damage.

Q. Is the check result normal?

Go to Step 4.
Repair or replace the connector, or repair the damaged harness wire.

STEP 4. M.U.T.-III data list



  • Data list reference table (Refer to ).

  1. Item 8: Manifold absolute pressure sensor

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Replace the engine-ECU.

STEP 5. M.U.T.-III data list



  • Data list reference table (Refer to ).

  1. Item 8: Manifold absolute pressure sensor

Q. Is the check result normal?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).
Go to Step 6.

STEP 6. Replace the manifold absolute pressure sensor



  • After replacing the manifold absolute pressure sensor, reconfirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

Replace the engine-ECU.
Check end.