DTC    P0403    Exhaust Gas Recirculation Control Circuit

for Preparation Click here


DESCRIPTION

Refer to DTC P0401 (Click here).

DTC No.
DTC Detection Condition
Trouble Area
P0403
Open or short in EGR valve circuit
(1-trip detection logic)
  1. Open or short in EGR circuit
  2. EGR valve assembly
  3. ECM

HINT:
DTC P0403 is set when the ignition switch is in the ON position.


WIRING DIAGRAM

Refer to DTC P0401 (Click here).

INSPECTION PROCEDURE

HINT:
Read freeze frame data using an intelligent tester. 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.

1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (OPERATE EGR VALVE)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the tester on.

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

  1. Perform the Active Test by referring to the table below.


Standard:

Tester Operation
Condition
Specified Condition
0 steps
Idling
Map value is 31 kPa with steady idling
0 to 30 steps
Idling
Map value is at least +10 to 15 kPa higher than when EGR valve is fully closed, and engine changes from steady to rough idling
30 steps or higher
Idling
Engine changes from rough idling to engine stall

Result 
Result
Proceed to
Outside standard range
A
Within standard range
B


NG
Go to step 2
OK

CHECK FOR INTERMITTENT PROBLEMS (Click here)  

2.INSPECT EGR VALVE ASSEMBLY
A202817E01

  1. Disconnect the EGR valve assembly connector.

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

Standard Resistance:
Tester Connection
Condition
Specified Condition
2 (+B1) - 1 (EGR4)
20 °C (68 °F)
18 to 22 Ω
2 (+B1) - 3 (EGR2)
20 °C (68 °F)
18 to 22 Ω
5 (+B2) - 4 (EGR1)
20 °C (68 °F)
18 to 22 Ω
5 (+B2) - 6 (EGR3)
20 °C (68 °F)
18 to 22 Ω

Text in Illustration 
*1
Component without harness connected:
(EGR Valve Assembly)

  1. Reconnect the EGR valve assembly connector.



NG
REPLACE EGR VALVE ASSEMBLY (Click here)
OK


3.INSPECT EGR VALVE ASSEMBLY (+B OR +B2 VOLTAGE)
A201052E01

  1. Disconnect the EGR valve assembly connector.

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

Standard Voltage:
Tester Connection
Switch Condition
Specified Condition
B49-2 (+B1) - Body ground
Ignition switch ON
11 to 14 V
B49-5 (+B2) - Body ground
Ignition switch ON
11 to 14 V

Text in Illustration 
*1
Front view of wire harness connector:
(to EGR Valve Assembly)

  1. Reconnect the EGR valve assembly connector.



NG
Go to step 6
OK


4.CHECK HARNESS AND CONNECTOR (ECM - EGR VALVE ASSEMBLY)
A202819E01

  1. Disconnect the EGR valve assembly connector.

  1. Disconnect the ECM connector.

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

Standard Resistance (Check for Open):
Tester Connection
Condition
Specified Condition
B8-51 (EGR1) - B49-4 (EGR1)
Always
Below 1 Ω
B8-50 (EGR2) - B49-3 (EGR2)
Always
Below 1 Ω
B8-49 (EGR3) - B49-6 (EGR3)
Always
Below 1 Ω
B8-48 (EGR4) - B49-1 (EGR4)
Always
Below 1 Ω

Standard Resistance (Check for Short):
Tester Connection
Condition
Specified Condition
B8-51 (EGR1) or B49-4 (EGR1) - Body ground
Always
 10 kΩ or higher
B8-50 (EGR2) or B49-3 (EGR2) - Body ground
Always
 10 kΩ or higher
B8-49 (EGR3) or B49-6 (EGR3) - Body ground
Always
 10 kΩ or higher
B8-48 (EGR4) or B49-1 (EGR4) - Body ground
Always
 10 kΩ or higher

Text in Illustration 
*1
Front view of wire harness connector:
(to EGR Valve Assembly)
*2
Front view of wire harness connector:
(to ECM)

  1. Reconnect the EGR valve assembly connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.READ DTC OUTPUT RECURS (DTC P0403)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Clear DTCs (Click here).

  1. Start the engine warm it up.

  1. Drive the vehicle for more than 10 minutes.

  1. Confirm on the vehicle that no DTC is set using the intelligent tester.

Result 
Result
Proceed to
P0403
A
No output
B


B
END
A

REPLACE ECM (Click here)  

6.CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - EGR VALVE ASSEMBLY)
A202820E01

  1. Disconnect the EGR valve assembly connector.

  1. Remove the integration relay from engine room relay block.

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

Standard Resistance (Check for open):
Tester Connection
Condition
Specified Condition
1F-10 - B49-2 (+B1)
Always
Below 1 Ω
1F-11 - B49-5 (+B2)
Always
Below 1 Ω

Standard Resistance (Check for short):
Tester Connection
Condition
Specified Condition
1F-10 or B49-2 (+B1) - Body ground
Always
 10 kΩ or higher
1F-11 or B49-5 (+B2) - Body ground
Always
 10 kΩ or higher

Text in Illustration 
*1
Front view of wire harness connector:
(to EGR Valve Assembly)
*2
Front view of wire harness connector:
(to Integration Relay)

  1. Reconnect the EGR valve assembly connector.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

CHECK FOR ECM POWER SOURCE CIRCUIT (Click here)