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 converts the manifold absolute pressure into a voltage signal 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
  • Battery positive voltage is 8 - 16 V
  • 2 seconds later after the ignition switch has been in "ON" position or the engine has started up
Judgment Criterion
  • The manifold absolute pressure sensor output voltage is 4.72 V or more.

FAIL-SAFE AND BACKUP FUNCTION



  • The pressure in the inlet manifold is controlled to be 100 kPa.
  • The EGR control is stopped (fully closed).
  • The fuel injection amount is restricted (Output restriction).
  • The turbocharger control is prohibited.
  • The open angle of the accelerator pedal is restricted.
  • The DPF regeneration is prohibited.
  • The throttle valve is opened (Electrical discontinuity).
  • The AS&G control is prohibited.

PROBABLE CAUSES



  • Failed manifold absolute pressure sensor
  • Open circuit in manifold absolute pressure sensor circuit or loose connector contact
  • Failed engine-ECU

DIAGNOSTIC PROCEDURE

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

  • Refer to Data List Reference Table .

  1. Item 6: 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 and measure at harness side.
  • Ignition switch: ON
  • 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

  • Refer to Data List Reference Table .

  1. Item 6: 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

  • Refer to Data List Reference Table .

  1. Item 6: 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 manifold absolute pressure sensor.