DTC Troubleshooting: P0403 (12)

DTC P0403:  EGR Valve Circuit Malfunction

1.Turn the ignition switch ON (II).

2.Do the DTC CLEAR in the CLEAR MENU with the HDS.

3.Start the engine.

4.Check fot Temporary DTCs or DTCs in the DTCs MENU with the HDS.

Is DTC P0403 indicated?


YES - Go to 5.


NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the EGR valve and the ECM.n


5.Turn the ignition switch OFF, and wait 10 seconds.

6.Disconnect the EGR valve 6P connector terminal No. 4 to body ground with a jumper wire.

7.Connect the EGR valve 6P connector terminal No. 4 to body ground with a jumper wire.

 

8.Connect the ECM test harness and the test pin box to the wire harness only, not to the ECM.

9.Check for continuity between test pin box terminal No. 124 and body ground.

Is there continuity?


YES - Go to 10.


NO - Repair open in the wire between the ECM connector No. 5 terminal No. 3 (test pin box terminal No. 124) and the EGR valve, then go to 15.


10.Connect the EGR valve 6P connector terminal No. 6 to body ground with a jumper wire.

 

11.Check for continuity between test pin box terminal No. 126 and body ground.

Is there continuity?


YES - Go to 12.


NO - Repair open in the wire between the ECM connector No. 5 terminal No. 5 (test pin box terminal No. 126) and the EGR valve, then go to 15.

12.At the EGR valve side, measure resistance between EGR valve 6P connector terminals No. 4 and No. 6.

 

Is there about 6.3-6.7 W at room termperature?


YES - Go to 21.


NO - Go to 13.


13.Turn the ignition switch OFF.

14.Replace the EGR valve.

15.Reconnect all connectors.

16.Turn the ignition switch ON (II).

17.Do the ECM RESET in the CLEAR MENU with the HDS.

18.Do the ETCS learn procedure.

19.Start the engine.

20.Check for temporary DTCs or DTCs in the DTCs MENU with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0403 is indicated, check for poor connections or loose terminals at the EGR vlave and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC troubleshooting.


NO - Troubleshooting is complete.n

21.Substitute a known-good ECM.

22.Start the engine.

23.Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0403 is indicated, check for poor connections or loose terminals at the EGR vlave and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC troubleshooting.


NO - Replace the original ECM.n