Diagnostic Method

Judge NG when the malfunction criteria below are completed.

Fig 1: Threshold Valve Table

Courtesy of SUBARU OF AMERICA, INC.

Timer for diagnosis after engine starting

1. Timer stop at fuel cut mode.

   During the driving conditions except a) above, timer count up by 4 milliseconds + TWCNT milliseconds at every 64 milliseconds.

Where, TWCNT is determined as follows,

TWCNT = 0 at idle switch ON,

TWCNT show on the following table at idle switch OFF.

Fig 2: Vehicle Speed Km/H (MPH) Table

Courtesy of SUBARU OF AMERICA, INC.

Judgment value of timer after engine starting

t = 455 - 27 X Ti

Ti is the lowest coolant temperature after starting the engine.

Time Needed for Diagnosis:  To be determined. (It is varied by the Min. engine coolant temperature and engine conditions such as vehicle speed and engine coolant temperature.)

Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.

Judge OK and clear the NG when the malfunction criteria below are completed.