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 - ] ).
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 / Data List / Primary / MAP and Throttle Idle Position.
7. Confirm that the Throttle Idle Position is ON and check the MAP value 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: 

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: 

NG 

REPLACE EGR VALVE ASSEMBLY 

(Refer to REMOVAL [10/2014 - ] )

Result: 

OK 

See step  3

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the EGR valve assembly connector.
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
   B49-2 (+B1) - Body ground	Power switch on (IG)	11 to 14 V
   B49-5 (+B2) - Body ground	Power switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

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

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
   B49-4 (EGR1) - B51-28 (EGR1)	Always	Below 1 Ω
   B49-3 (EGR2) - B51-27 (EGR2)	Always	Below 1 Ω
   B49-6 (EGR3) - B51-26 (EGR3)	Always	Below 1 Ω
   B49-1 (EGR4) - B51-25 (EGR4)	Always	Below 1 Ω
   B49-4 (EGR1) or B51-28 (EGR1) - Body ground	Always	10 kΩ or higher
   B49-3 (EGR2) or B51-27 (EGR2) - Body ground	Always	10 kΩ or higher
   B49-6 (EGR3) or B51-26 (EGR3) - Body ground	Always	10 kΩ or higher
   B49-1 (EGR4) or B51-25 (EGR4) - Body ground	Always	10 kΩ or higher

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 No. 1 integration relay from the 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
   B49-2 (+B1) - 1A-8	Always	Below 1 Ω
   B49-5 (+B2) - 1A-8	Always	Below 1 Ω
   B49-2 (+B1) or 1A-8 - Body ground	Always	10 kΩ or higher
   B49-5 (+B2) or 1A-8 - Body ground	Always	10 kΩ or higher

Result: 

OK 

REPLACE NO. 1 INTEGRATION RELAY 

(Refer to REMOVAL [10/2014 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR