DTC P0403 Exhaust Gas Recirculation (EGR) Motor Control Circuit (4JJ3 with DPD)

1. DTC P0403 description

The EGR valve is equipped with a microprocessor. The internal microprocessor controls the EGR motor according to the commands from the ECM. The ECM calculates the desired EGR position based on the driving condition of the engine, and sends it to the EGR valve via CAN. The EGR valve lift amount is calculated by the microprocessor inside the EGR valve, and is sent to the ECM via CAN. The EGR valve has the following circuits.

  • Ignition power supply circuit
  • CAN High circuit
  • CAN Low circuit
  • Ground circuit

The EGR valve and ECM communicate the control information and diagnosis information via the CAN communication circuit. The microprocessor diagnoses problems inside the EGR valve. If the ECM receives a failure message from the EGR valve, the DTC is set.

2. Condition for setting DTC P0403

Condition for running the DTC

  • The battery voltage is 10 to 16 V.
  • DTCs U0074 and U010A are not set.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC U0074 Control Module Communication Bus Off - Local CAN".

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC U010A Lost Communication With Exhaust Gas Recirculation (EGR) Control Module".

Condition for setting the DTC

  • The ECM detects that a failure message from the EGR valve is received for 2 seconds or more.

3. Action taken when DTC P0403 sets

  • The ECM illuminates the MIL. Refer to Action taken when DTC sets - Type A.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".

  • The ECM limits the fuel injection quantity.
  • The ECM inhibits the EGR control.
  • The ECM inhibits the cruise control.

4. Condition for clearing DTC P0403

  • Refer to Conditions for clearing the MIL/DTC - Type A or Type B.

Refer to "51.Engine Control 1A.Troubleshooting(4JJ3 with DPD) DTC type definitions".

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