Procedure For DTC P0406

With GST 

1. Start engine and warm it up to normal operating temperature.
2. Confirm that EGR valve is not lifting. If NG, perform trouble diagnosis for DTC P1402. Refer to DTC P1402 EGR FUNCTION .
   Fig 1: Lifting EGR Valve

   Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check voltage between ECM terminal 63 (EGR temperature sensor signal) and engine ground at about 1, 500 RPM with EGR valve lifted up to the full position by hand.

   Voltage should decrease to less than 1.5V. 

4. If NG, go to "DIAGNOSTIC PROCEDURE ".

   If OK, perform trouble diagnoses for DTC P0400 and P1400.

   Refer to P0400 DTC P0400 EGR FUNCTION  and P1400 DTC P1400 EGRC-SOLENOID VALVE .

Fig 2: Checking Voltage Between ECM Terminal 63 And Engine Ground

Courtesy of NISSAN MOTOR CO., U.S.A.