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P0406

DTC P0406: EGR Valve Position Sensor Circuit High Voltage

1. Turn the ignition switch ON (II).
2. Check the EGR VLS in the DATA LIST with the HDS.

Is 4.88 V or higher indicated?

YES - Go to step 3.

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

3. Turn the ignition switch OFF.
4. Disconnect the EGR valve 6P connector.
5. Turn the ignition switch ON (II).




6. Measure voltage between EGR valve 6P connector terminals No. 2 and No. 3.

Is there about 5 V?

YES - Go to step 8.

NO - Go to step 7.




7. Measure voltage between ECM/PCM connector terminals A20 and A23.

Is there about 5 V?

YES - Repair open in the wire between the EGR valve and the ECM/PCM (A23), then go to step 10

NO - Go to step 14.

8. Turn the ignition switch OFF.
9. Replace the EGR valve.
10. Turn the ignition switch ON (II).
11. Reset the ECM/PCM with the HDS.
12. Do the ECM/PCM idle learn procedure. Programming and Relearning
13. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P0406 is indicated, check for poor connections or loose terminals at the EGR valve and the ECM/PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Troubleshooting is complete.

14. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.
15. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P0406 is indicated, check for poor connections or loose terminals at the EGR valve and the ECM/PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.