Diagnostic Method

Measure the pressure in the following procedures when the enable conditions are completed, and then diagnosis by calculating the result.

1. PMOF1 is equal to the intake manifold pressure at enable condition completed, and EGR target step is set to 50 steps (almost fully opened).
2. PMON is equal to the intake manifold pressure in 1 second after EGR target step is set 50 steps (when enable conditions are completed), and EGR target step is set to 0 step.
3. PMOF2 is equal to the intake manifold pressure in 1 second after EGR target step is set to 0 step (in 2 seconds after enable conditions are completed).
   Fig 1: Enable Conditions Graph

   Courtesy of SUBARU OF AMERICA, INC.
4. Calculate the judged value using the following formula.

   Judged value = [PMON - (PMOF1 + PMOF2)/2]

   Judge NG when the malfunction criteria bellows are completed. Judge OK and clear NG when the malfunction criteria bellows are not completed.

   Judgment Value 

   Fig 2: Threshold Value Table

   Courtesy of SUBARU OF AMERICA, INC.
   1. Time Needed for Diagnosis:  3 seconds
   2. Malfunction Indicator Light Illumination:  2 continuous driving cycles.