ECD SYSTEM (w/o DPF), Diagnostic DTC:P0622

DTC Code DTC Name
P0622 Generator Field "F" Terminal Circuit

DESCRIPTION

While the generator is generating current, a duty signal is sent from terminal M of the generator to the ECM terminal ALT. The duty signal indicates density of field current flowing through the rotor coil of the generator, and the ratio of the duty signal is high when the voltage generated from the generator is high. The ECM uses this duty signal to determine if the generator is operating.

The ECM will detect a generator failure or an open malfunction of the circuit, if the duty signal is not output from terminal M of the generator, although the engine is running.

A01BGN6E01
DTC No. DTC Detection Condition Trouble Area
P0622

No duty signal from terminal M of generator at engine running

(1 trip detection logic)


  • Open in generator circuit

  • Generator

  • ECM

WIRING DIAGRAM

A01BHBEE01

INSPECTION PROCEDURE

Tech Tips


  • If different DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.

  • Read freeze frame data using an intelligent tester. Freeze frame data record 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, if the air-fuel ratio was lean or rich, and other data, from the time the malfunction occurred.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0622)


    1. Connect an intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester ON.

    3. Select the following menu items: Powertrain / Engine / DTC.

    4. Read DTCs.

      Result
      Display (DTC Output) Proceed To
      P0622 A
      P0622 and other DTCs B

    B
    A
  2. CHECK WHETHER DTC OUTPUT RECURS (DTC P0622)


    1. Connect an intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester ON.

    3. Select the following menu items: Powertrain / Engine / DTC / Clear.

    4. Clear DTCs.

    5. Start the engine.

    6. Allow the engine to idle for 1 minute or more.

    7. Select the following menu items: Powertrain / Engine / DTC.

    8. Read DTCs.

      Result
      Display (DTC Output) Proceed To
      P0622 A
      No output B

    B
    A
  3. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - GENERATOR - ECM)


    1. A01BFUUE02

      Disconnect the D6 generator connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage of the generator connector.

      Standard voltage
      Tester Connection Specified Condition
      IG (D6-2) - Body ground 11 to 14 V
    4. Turn the ignition switch to OFF.

    5. Disconnect the D1 ECM connector.

    6. Measure the resistance of the harness side connectors.

      Standard resistance (Check for open)
      Tester Connection Specified Condition
      M (D6-3) - ALT (D1-8) Below 1 Ω
      Standard resistance (Check for short)
      Tester Connection Specified Condition
      M (D6-3) or ALT (D1-8) - Body ground 10 kΩor higher
    7. Reconnect the generator connector.

    8. Reconnect the ECM connector.


    NG
    OK
  4. INSPECT GENERATOR ASSEMBLY (GENERATOR ROTOR)


    1. A01BDJYE01

      Remove the generator assembly Click here.

    2. Remove the generator rotor assembly Click here.

    3. Measure the resistance between the slip rings of generator rotor.

      Standard resistance
      Tester Connection Condition Specified Condition
      Generator slip rings 20°C(68°F) 2.3 to 2.7 Ω
    4. A01BFBIE01

      Measure the resistance between the slip ring and generator rotor assembly.

      Standard resistance
      Tester Connection Specified Condition
      Generator slip ring - Generator rotor 10 kΩ or higher
    5. A01BHJG

      Inspect the slip rings of the generator rotor.


      1. Check that the slip rings are not rough or scored.

      2. Measure the slip ring diameter.

        Standard diameter
        14.2 to 14.4 mm (0.559 to 0.567 in.)
        Minimum diameter
        14.0 mm (0.551 in.)

    NG
    OK
  5. REPLACE GENERATOR ASSEMBLY


    1. Replace the generator assembly Click here.


    NEXT
  6. REPLACE GENERATOR ROTOR ASSEMBLY


    1. Replace the generator rotor assembly Click here.


    NEXT
  7. CHECK WHETHER DTC OUTPUT RECURS (DTC P0622)


    1. Connect an intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester ON.

    3. Select the following menu items: Powertrain / Engine / DTC / Clear.

    4. Clear DTCs.

    5. Start the engine.

    6. Allow the engine to idle for 1 minute or more.

    7. Select the following menu items: Powertrain / Engine / DTC.

    8. Read DTCs.

      Result
      Display (DTC Output) Proceed To
      P0622 A
      No output B

    B
    A