ECD SYSTEM(w/ Glow Plug Controller), Diagnostic DTC:P1609

DTC Code DTC Name
P1609 Air Fuel Ratio Too Rich

DESCRIPTION

This DTC is stored if the ECM detects that the air fuel ratio is too rich due to a malfunction in the fuel system, mass air flow meter or diesel turbo pressure sensor.

Using the GTS, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory
P1609 Air Fuel Ratio Too Rich

Both of the following conditions 1 and 2 are met for approximately 2 seconds: (1 trip detection logic)


  1. All of the following conditions are met:


    • Engine not being started

    • Air fuel ratio sensor is active (warmed up)

    • Mass air flow meter is normal

    • Diesel turbo pressure sensor is normal

    • PM automatic regeneration control has not been performed

  2. Air fuel ratio sensor output value exceeds the threshold

  • Intake system clogged

  • Electric EGR control valve assembly stuck closed

  • Deterioration of mass air flow meter (out of range)

  • Intake system hose disconnected or cracked

  • Turbocharger sub-assembly vane stuck fully open

  • Diesel turbo pressure sensor

  • Atmospheric pressure sensor (built into ECM)

  • Suction control valve (built into supply pump assembly) sticking

  • Fuel leak

  • Fuel pressure sensor (built into common rail assembly)

  • Engine coolant leak

  • Radiator assembly clogged

  • Engine coolant temperature sensor

  • Engine coolant temperature sensor out of range or stuck

 - DTC stored

CAUTION / NOTICE / HINT

Tech Tips


  • B0044SNE02
    *a DTC stored
    *b 0.5 seconds
    *c Freeze frame data recorded point

  • In contrast to normal malfunction diagnosis for components, circuits and systems, DTC P1609 is used to determine the malfunctioning area from the problem symptoms and freeze frame data when the user mentions problems such as black smoke or white smoke being emitted.

    As this DTC can be stored as a result of certain user actions, even if this DTC is output, if the customer makes no mention of problems, clear this DTC without performing any troubleshooting and return the vehicle to the customer.

  • If any other DTCs are output, perform troubleshooting for those DTCs first.

  • Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

  • When confirming the freeze frame data, be sure to check all 5 sets of freeze frame data.

  • The fourth set of freeze frame data is the data recorded when the DTC is stored.

PROCEDURE


  1. READ OUTPUT DTC (RECORD STORED DTC AND FREEZE FRAME DATA (PROCEDURE 1))


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    4. Record the stored DTCs and freeze frame data.


      Powertrain > Engine and ECT > Trouble Codes

      Tech Tips

      This freeze frame data shows the actual engine conditions when air fuel ratio too rich problem occurred.

      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P1609)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

    4. Read the DTCs.


      Powertrain > Engine and ECT > Trouble Codes
      Result
      Result Proceed to
      DTC P1609 is output A
      DTC P1609 and other DTCs are output B

      Tech Tips

      If any DTCs other than DTC P1609 are output, troubleshoot those DTCs first.


    A

    GO TO BLACK SMOKE EMITTED Click here

    B

    GO TO DTC CHART Click here