DTC P0403: Exhaust Gas Recirculation Control Circuit: Procedure

1. Connect the Techstream to the DLC3.
2. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

   HINT: 

   • When performing the Active Test, make sure the shift lever is in P or N.
   • The A/C switch and all accessory switches should be off.
3. Turn the Techstream on.
4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.
5. Confirm that Throttle Idle Position is ON and check the engine idling condition and the value of MAP 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.

   OK

   MAP and idling condition change in response to EGR step position as follows.

   Standard

   -	EGR Step Position (Active Test)
   	Step 0	Step 0 to 30
   Idling condition	Steady idling	Idling changes from steady to rough idling or engine stalls
   MAP (Data List)	20 to 40 kPa (150 to 300 mmHg)	MAP value is at least 10 kPa (75 mmHg) higher than when EGR valve is fully closed

NG → See step   2 

OK → See step   7 

1. Inspect the EGR valve assembly. Refer to INSPECTION - Step 1 .

NG → See step   8 

OK: Go to next step 

Fig 1: Identifying C43 EGR Valve Assembly Connector Terminals (+B / +B2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the EGR valve connector.
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   C43-5 (+B1) - Body ground	Engine switch on (IG)	11 to 14 V
   C43-2 (+B2) - Body ground	Engine switch on (IG)	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

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

3. Reconnect the EGR valve connector.

NG → See step   6 

OK: Go to next step 

1. Disconnect the EGR valve 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
   C28-23 (EGR1) - C43-4 (EGR1)	Always	Below 1 Ω
   C28-36 (EGR2) - C43-3 (EGR2)	Always	Below 1 Ω
   C28-30 (EGR3) - C43-6 (EGR3)	Always	Below 1 Ω
   C28-24 (EGR4) - C43-1 (EGR4)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   C28-23 (EGR1) or C43-4 (EGR1) - Body ground	Always	10 kΩ or higher
   C28-36 (EGR2) or C43-3 (EGR2) - Body ground	Always	10 kΩ or higher
   C28-30 (EGR3) or C43-6 (EGR3) - Body ground	Always	10 kΩ or higher
   C28-24 (EGR4) or C43-1 (EGR4) - Body ground	Always	10 kΩ or higher

4. Reconnect the EGR valve connector.
5. Reconnect the ECM connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the engine switch on (IG) and turn the Techstream on.
3. Clear DTCs. Refer to DTC CHECK / CLEAR .
4. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
5. Confirm that no DTC is output using the Techstream.
   RESULT
   
   

   Result	Proceed to
   DTC P0403 output	A
   No DTC output	B

B → END 

A → See step   10 

1. Disconnect the EGR valve connector.
2. Remove the No. 1 integration relay from engine room relay block.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance (Check for Open)

   Tester Connection	Condition	Specified Condition
   1B-4 - C43-5 (+B1)	Always	Below 1 Ω
   1B-4 - C43-2 (+B2)	Always	Below 1 Ω

   Standard Resistance (Check for Short)

   Tester Connection	Condition	Specified Condition
   1B-4 or C43-5 (+B1) - Body ground	Always	10 kΩ or higher
   1B-4 or C43-2 (+B2) - Body ground	Always	10 kΩ or higher

4. Reconnect the EGR valve connector.
5. Reinstall the No. 1 integration relay.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   9