ECD SYSTEM DPF Switch and Buzzer Circuit

DESCRIPTION

The DPF (Diesel Particulate Filter) is controlled by the ECM to activate the forcible regeneration function automatically. However, depending on driving conditions, the forcible regeneration function may not be activated. In such a case, the indicator light on the combination meter and the DPF switch light blink to inform the driver. When the DPF switch is pressed with the vehicle stopped, RGSW signals will be input into the ECM and the forcible regeneration function will activate.

If the vehicle continues to be driven without performing forcible regeneration while the indicator light is ON, a buzzer intermittently sounds to inform the driver.

Tech Tips

If the buzzer intermittently sounds, the brake vacuum warning switch may have been turned on.

In this case, inspect the brake vacuum warning switch circuit first.

A01CH30E01

WIRING DIAGRAM

A01CISBE02

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK BUZZER OPERATION


    1. Check the buzzer sounds.

      Result
      Sounds Proceed to
      The buzzer sounds intermittently A
      The buzzer sounds continuously B

    B

    CHECK BRAKE VACUUM WARNING BUZZER CIRCUIT

    A

  2. CHECK DPF SWITCH (POWER SOURCE)


    1. A01CJAKE02

      Disconnect the DPF switch connector.

    2. Turn the ignition switch to the ON position.

    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage
      Tester Connection Condition Specified Condition
      D21-6 - Body ground Ignition switch in the ON position 18 to 27 V
      D21-2 - Body ground Ignition switch in the ON position 18 to 27 V

    4. Turn the ignition switch off.

    5. Reconnect the DPF switch connector.


    NG

    INSPECT DPF SWITCH ASSEMBLY (ILLUMINATED) Click here

    OK

  3. INSPECT DPF SWITCH ASSEMBLY (RESISTANCE)


    1. A01CHMCE04

      Disconnect the DPF switch connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      D21-6 - D21-7 DPF switch on Below 1 Ω
      D21-6 - D21-7 DPF switch off 10 kΩ or higher

    3. Reconnect the DPF switch connector.


    NG

    REPLACE DPF SWITCH ASSEMBLY

    OK

  4. INSPECT DPF SWITCH ASSEMBLY (ILLUMINATED)


    1. A01CHMCE04

      Remove the DPF switch.

    2. Check that the illumination comes on.

      Result
      Connector Connection Condition Illumination
      Apply the battery voltage terminal D-21 (+) and D21-3 (-) Always Comes on

    3. Reinstall the DPF switch.


    NG

    REPLACE DPF SWITCH ASSEMBLY

    OK

  5. CHECK HARNESS AND CONNECTOR (DPF SWITCH - ECM)


    1. A01CI2TE01

      Disconnect the DPF switch connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Check for open
      Tester Connection Condition Specified Condition
      D21-7 - E24-15 (RGSW) Always Below 1 Ω
      D21-3 - E25-10 (W2) Always Below 1 Ω
      Check for short
      Tester Connection Condition Specified Condition
      D21-7 or E24-15 (RGSW) - Body ground Always 10 kΩ or higher
      D21-3 or E25-10 (W2) - Body ground Always 10 kΩ or higher

    4. Reconnect the DPF switch connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (DPF SWITCH - ECM)

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

  6. INSPECT FUSE (ECU-IG FUSE)


    1. A01CIKVE01

      Remove the ECU-IG fuse from the No. 1 relay block.

    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      1 - 2 Always Below 1 Ω

    3. Reinstall the ECU-IG fuse.


    NG

    REPLACE FUSE (ECU-IG FUSE)

    OK

  7. CHECK HARNESS AND CONNECTOR (DPF SWITCH - IGNITION SWITCH)


    1. A01CHAWE04

      Disconnect the DPF switch connector.

    2. Disconnect the ignition switch connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Check for open
      Tester Connection Condition Specified Condition
      D21-6 - I6-10 (IG1) Always Below 1 Ω
      D21-2 - I6-10 (IG1) Always Below 1 Ω
      Check for short
      Tester Connection Condition Specified Condition
      D21-6 or I6-10 (IG1) - Body ground Always 10 kΩ or higher
      D21-2 or I6-10 (IG1) - Body ground Always 10 kΩ or higher

    4. Reconnect the DPF switch connector.

    5. Reconnect the ignition switch connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (DPF SWITCH - IGNITION SWITCH ASSEMBLY)

    OK

  8. INSPECT IGNITION SWITCH ASSEMBLY


    1. A01CHNME03

      Disconnect the ignition switch connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Ignition Switch Position Specified Condition
      All terminals LOCK 10 kΩ or higher
      I6-9 (AM1) - I6-10 (IG1) ON Below 1 Ω

    3. Reconnect the ignition switch connector.


    NG

    REPLACE IGNITION SWITCH ASSEMBLY

    OK

  9. INSPECT FUSE (AM1 FUSE)


    1. A01CIJFE01

      Remove the AM1 fuse.

    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      1 - 2 Always Below 1 Ω

    3. Reinstall the AM1 fuse.


    NG

    REPLACE FUSE (AM1 FUSE)

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH ASSEMBLY - BATTERY)