DTC P0403: Exhaust Gas Recirculation Control Circuit [10/2014 - ]: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Put the engine in inspection mode (maintenance mode).

   Refer to INSPECTION MODE PROCEDURE [10/2014 - ]

   Powertrain > Hybrid Control > Utility 

   Tester Display
   Inspection Mode

5. 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.

6. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position / Primary / MAP and Throttle Idle Position.

   Powertrain > Engine and ECT > Active Test 

   Active Test Display
   Control the EGR Step Position

   Data List Display
   MAP
   Throttle Idle Position

7. Confirm that the Throttle Idle Position is ON and check the MAP values in the Data List while performing the Active Test.

   HINT: 

   • 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

   MAP change in response to EGR step position when Throttle Idle Position is ON in Data List.

   Standard

   -	EGR Step Position (Active Test)
   	0 Steps	0 to 30 Steps
   MAP (Data List)	(EGR valve is fully closed)	MAP value is at least +10 kPa (75 mmHg) higher than when EGR valve is fully closed

   HINT: 

   • While performing the Active Test, if the increase in the value of MAP is small, the EGR valve assembly may be a malfunctioning.
   • Even if the EGR valve assembly is malfunctioning, rough idling or an increase in the value of MAP may occur while performing the Active Test. However, the amount that the value of MAP increases will be smaller than normal.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [10/2014 - ] 

Result: 

NG 

See step  2

1. Inspect the EGR valve assembly.

   Refer to INSPECTION [10/2014 - ]

   HINT: 

   Perform "Inspection After Repair" after replacing the EGR valve assembly.

   Refer to INITIALIZATION [10/2014 - ]

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE EGR VALVE ASSEMBLY. Refer to  REMOVAL [10/2014 - ] 

Result: 

OK 

See step  3

1. Disconnect the EGR valve assembly connector.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to EGR Valve Assembly)

2. Turn the power switch on (IG).
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   C40-2 (+B1) - Body ground	Power switch on (IG)	11 to 14 V
   C40-5 (+B2) - Body ground	Power switch on (IG)	11 to 14 V

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  5

Result: 

OK 

See step  4

1. Disconnect the EGR valve assembly connector.
2. Disconnect the ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C40-4 (EGR1) - C48-28 (EGR1)	Always	Below 1 Ω
   C40-3 (EGR2) - C48-27 (EGR2)	Always	Below 1 Ω
   C40-6 (EGR3) - C48-26 (EGR3)	Always	Below 1 Ω
   C40-1 (EGR4) - C48-25 (EGR4)	Always	Below 1 Ω
   C40-4 (EGR1) or C48-28 (EGR1) - Body ground	Always	10 kΩ or higher
   C40-3 (EGR2) or C48-27 (EGR2) - Body ground	Always	10 kΩ or higher
   C40-6 (EGR3) or C48-26 (EGR3) - Body ground	Always	10 kΩ or higher
   C40-1 (EGR4) or C48-25 (EGR4) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE ECM. Refer to  REMOVAL [10/2014 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Disconnect the EGR valve assembly connector.
2. Remove the EFI-MAIN relay from the No. 1 engine room relay block and junction block assembly.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   3 (EFI-MAIN relay) - C40-2 (+B1)	Always	Below 1 Ω
   3 (EFI-MAIN relay) - C40-5 (+B2)	Always	Below 1 Ω
   3 (EFI-MAIN relay) or C40-2 (+B1) - Body ground	Always	10 kΩ or higher
   3 (EFI-MAIN relay) or C40-5 (+B2) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

GO TO ECM POWER SOURCE CIRCUIT. Refer to  ECM Power Source Circuit [10/2014 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR