Diagnostic Method: Notes

<Timer diagnosis> 

Start the count up operation of counters in ECM and in soaking timer IC when the engine is started.

Judge as timer malfunction if the difference between the counter in ECM and counter in soaking timer IC exceeds the allowable limit when the ignition switch is OFF.

Fig 1: ECM Internal Engine Driving Pattern (Timer Diagnosis)

Courtesy of SUBARU OF AMERICA, INC.

Judge as NG when the following conditions are established.

<Full count diagnosis> 

Reset the counter in soaking timer IC and start the count up operation.

Judge as full count diagnosis malfunction if counter in soaking timer IC is not $3FF (1023 count) after 4 seconds.

Fig 2: ECM Internal Engine Driving Pattern (Full Count Diagnosis)

Courtesy of SUBARU OF AMERICA, INC.

Judge as NG when the following conditions are established.