DTC P0403-18: Exhaust Gas Recirculation "A" Circuit Current Below Threshold; DTC P0403-19: Exhaust Gas Recirculation "A" Circuit Current Above Threshold; DTC P1400-18: Exhaust Gas Recirculation "A" Control Circuit 2 Circuit Current Below Threshold; DTC P1400-19: Exhaust Gas Recirculation "A" Control Circuit 2 Circuit Current Above Threshold [08/2023 - ]: Procedure

Pre-procedure1

• Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

  HINT: 

  The A/C switch and all accessory switches should be off.

  Powertrain > Engine > Data List 

  Tester Display
  Coolant Temperature

• Confirm that the value of Data List item Engine Independent is "Operate" then check the value of Intake Manifold Absolute Pressure while performing the Active Test.

  Powertrain > Engine > Active Test 

  Active Test Display
  Control the EGR Step Position

  Data List Display
  Intake Manifold Absolute Pressure
  Engine Independent

  NOTE:

  • Make sure that the value of Data List item Engine Independent is "Operate" while performing the Active Test.
  • Do not leave the EGR valve open for 10 seconds or more during the Active Test.
  • Be sure to return the EGR valve to step 0 when the Active Test is completed.
  • Do not open the EGR valve 30 steps or more during the Active Test.

  OK

  The value of Intake Manifold Absolute Pressure changes in response to the EGR step position when the value of Engine Independent is "Operate".

  Standard

  -	Control the EGR Step Position (Active Test)
  	0 Steps	0 to 30 Steps
  Intake Manifold Absolute Pressure (Data List)	(EGR valve is fully closed)	Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed

  HINT: 

  • If the value of Data List item Engine Independent is "Not Opr" when the engine is idling, charge control is being performed. Perform the Active Test after charge control is complete ("Operate" is displayed).
  • While performing the Active Test, if the increase in the value of Intake Manifold Absolute Pressure is small, the EGR valve assembly may be malfunctioning.
  • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of Intake Manifold Absolute Pressure may occur while performing the Active Test. However, the amount that the value of Intake Manifold Absolute Pressure increases will be smaller than normal.

  Result

  Result	Proceed to
  Intake Manifold Absolute Pressure value is at least +10 kPa (1.45 psi) higher than when EGR valve is fully closed	A
  None of the above conditions are met	B

Post-procedure1

• None.

Result: 

A 

CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [10/2022 - ] 

Result: 

B 

See step  2

Refer to INSPECTION [10/2022 - ]

Result

Result: 

NG 

REPLACE EGR VALVE ASSEMBLY. Refer to  REMOVAL [08/2023 - ] 

Result: 

OK 

See step  3

Pre-procedure1

• Disconnect the EGR valve assembly connector.
• Disconnect the ECM connector.

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

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  B79-1 (EGA+) - B28-3 (EGA+)	Always	Below 1 Ω	Ω
  B79-2 (EGA-) - B28-4 (EGA-)	Always	Below 1 Ω	Ω
  B79-4 (EGB+) - B28-6 (EGB+)	Always	Below 1 Ω	Ω
  B79-3 (EGB-) - B28-5 (EGB-)	Always	Below 1 Ω	Ω
  B79-1 (EGA+) or B28-3 (EGA+) - Body ground and other terminals	Always	10 kΩ or higher	kΩ
  B79-2 (EGA-) or B28-4 (EGA-) - Body ground and other terminals	Always	10 kΩ or higher	kΩ
  B79-4 (EGB+) or B28-6 (EGB+) - Body ground and other terminals	Always	10 kΩ or higher	kΩ
  B79-3 (EGB-) or B28-5 (EGB-) - Body ground and other terminals	Always	10 kΩ or higher	kΩ

  Result

  Proceed to
  OK
  NG

Post-procedure1

• None.

Result: 

OK 

REPLACE ECM. Refer to  REMOVAL [08/2023 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR