ECD SYSTEM(w/ DPF), 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, exhaust fuel addition injector system, mass air flow meter sub-assembly or manifold absolute 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.

P1609
DTC Detection Drive Pattern DTC Detection Condition Trouble Area
-

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 sub-assembly is normal

    • Manifold absolute pressure sensor is normal

    • PM forced regeneration has not been performed

  2. Air fuel ratio sensor output value exceeds the threshold


  • Intake system clogged

  • EGR valve stuck open

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

  • Intake system hose disconnected or cracked

  • Turbocharger sub-assembly vane stuck fully open

  • Manifold absolute pressure sensor

  • Atmospheric pressure sensor (built into ECM)

  • Suction control valve sticking

  • Fuel leak

  • Excessive amount of engine oil

  • Fuel pressure sensor (common rail assembly (for bank 1))

  • Engine coolant leak

  • Radiator assembly clogged

  • Engine coolant temperature sensor

  • Engine coolant temperature sensor out of range or stuck

  • Exhaust fuel addition injector assembly stuck open

  • Air fuel ratio sensor circuit contact problem

  • Fuel (cetane number, evaporation, etc.)

CAUTION / NOTICE / HINT


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: Engine and ECT / Trouble Codes.

    4. Record the stored DTC and freeze frame data.

      Tech Tips

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


    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: Engine and ECT / Trouble Codes.

    4. Read the DTCs.

      Result
      Result Proceed to
      P1609 is output A
      P1609 and other DTCs are output B

      Tech Tips

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


    A
    B