P0106 – Manifold Absolute Pressure Sensor Range-Performance Problem MMC L200 IV



OPERATION

  • A power voltage of 5 V is applied to the manifold absolute pressure sensor power terminal (terminal No. 1) from the engine-ECU (terminal No. 72) and earthed to the engine-ECU (terminal No. 31) from the manifold absolute pressure sensor (terminal No. 3).
  • The sensor signal is inputted to the engine-ECU (terminal No. 37) from the manifold absolute pressure sensor output terminal (terminal No. 2).

  • 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 JUDGEMENT

  • 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.
  • The following 3 conditions are formed:
  • The engine cooling water temperature is from -5 to 80 °C.
  • The air intake temperature is from -5 to 80 °C.
  • The atmospheric pressure is from 76 to 120 kPa.
  • When an idle state and an engine rotation speed of 2,000 r/min continue for three seconds, manifold absolute pressures are read and the difference between them goes under 800 Pa for 1 second.

  • PROBABLE CAUSES

  • Failed manifold absolute pressure sensor
  • Manifold absolute pressure sensor circuit harness damage or loose connector contact.
  • EGR cooler clogged.
  • EGR pipe (A, B) clogged.
  • Failed engine-ECU

  • DIAGNOSIS PROCEDURE

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

  • Item 6: Manifold absolute pressure sensor
  • Q. Is the check result normal?

    STEP 2. Connector check: A-105 manifold absolute pressure sensor connector

    Q. Is the check result normal?

    STEP 3. Perform voltage measurement at A-105 manifold absolute pressure sensor connector.

  • Use special tool test harness (MB991709) to connect connector, and measure at pick-up harness.
  • Ignition switch: ON
  • Voltage between terminal No. 1 and earth.
  • Q. Is the check result normal?

    STEP 4. Connector check: C-105 engine-ECU connector

    Q. Is the check result normal?

  • Check power supply line for damage.
  • STEP 5. Perform voltage measurement at A-105 manifold absolute pressure sensor connector.

  • Use special tool harness (MB991709) to connect connector, and measure at pick-up harness.
  • Ignition switch: ON
  • Voltage between terminal No. 3 and earth.
  • Q. Is the check result normal?

    STEP 6. Connector check: C-105 engine-ECU connector

    Q. Is the check result normal?

  • Check earthing line for damage.
  • STEP 7. Perform voltage measurement at A-105 manifold absolute pressure sensor connector.

  • Use special tool harness (MB991709) to connect connector, and measure at pick-up harness.
  • Ignition switch: ON
  • Voltage between terminal No. 2 and earth.
  • Q. Is the check result normal?

    STEP 8. Perform voltage measurement at C-105 engine-ECU connector.

  • Measure engine-ECU terminal voltage.
  • Ignition switch: ON
  • Voltage between terminal No. 37 and earth.
  • Q. Is the check result normal?

  • Check output line for damage.
  • STEP 9. Connector check: C-105 engine-ECU connector

    Q. Is the check result normal?

    STEP 10. Check on clogged EGR cooler.

  • Check whether the EGR cooler is being clogged or not.
  • Q. Is the check result normal?

    STEP 11. Check on clogged EGR pipe (A, B).

  • Check whether the EGR pipe (A, B) is being clogged or not.
  • Q. Is the check result normal?

    STEP 12. M.U.T.-III data list

  • Item 6: Manifold absolute pressure sensor
  • Q. Is the check result normal?

    Author: admin