P0403

1UR-FE ENGINE CONTROL: SFI SYSTEM: P0403: Exhaust Gas Recirculation Control Circuit
P0403 - Exhaust Gas Recirculation Control Circuit

DESCRIPTION

Refer to DTC P0401 P0401.





HINT
DTC P0403 is stored when the engine switch is on (IG).

MONITOR DESCRIPTION

This DTC is designed to detect an open or short in the EGR valve circuit.

If the EGR terminal voltage is low when the EGR terminal output is off, the ECM determines that the EGR valve circuit is malfunctioning.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

2. Turn the engine switch on (IG) and turn the Techstream on [A].

3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.

4. Start the engine and warm it up [B].

5. Drive the vehicle at 20 km/h (12 mph) or more for 10 minutes [C].

CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.

6. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [D].

7. Read the pending DTCs.

HINT
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.

8. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

9. Input the DTC: P0403.

10. Check the DTC judgment result.





HINT
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.

11. If the judgment result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P0401 P0401.

INSPECTION PROCEDURE

HINT
Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE EGR VALVE)

(a) Connect the Techstream to the DLC3.

(b) 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.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.

(e) 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:





NG -- INSPECT EGR VALVE ASSEMBLY

OK -- CHECK FOR INTERMITTENT PROBLEMS Check For Intermittent Problems

2. INSPECT EGR VALVE ASSEMBLY

(a) Inspect the EGR valve assembly Testing and Inspection.

NG -- REPLACE EGR VALVE ASSEMBLY Removal
OK -- Continue to next step.

3. INSPECT EGR VALVE ASSEMBLY (+B OR +B2 VOLTAGE)





(a) Disconnect the EGR valve connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





Text in Illustration





(c) Reconnect the EGR valve connector.

NG -- CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - EGR VALVE)
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (ECM - EGR VALVE)

(a) Disconnect the EGR valve connector.

(b) Disconnect the ECM connector.

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

Standard Resistance (Check for Open):





Standard Resistance (Check for Short):





(d) Reconnect the EGR valve connector.

(e) Reconnect the ECM connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. CHECK WHETHER DTC OUTPUT RECURS (DTC P0403)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG) and turn the Techstream on.

(c) Clear DTCs Reading and Clearing Diagnostic Trouble Codes.

(d) Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

(e) Confirm that no DTC is output using the Techstream.

Result





B -- END

A -- REPLACE ECM Removal

6. CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - EGR VALVE)

(a) Disconnect the EGR valve connector.

(b) Remove the No. 1 integration relay from engine room relay block.

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

Standard Resistance (Check for Open):





Standard Resistance (Check for Short):





(d) Reconnect the EGR valve connector.

(e) Reinstall the No. 1 integration relay.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- CHECK ECM POWER SOURCE CIRCUIT ECM Power Source Circuit