< 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/PCM Internal Engine Diagnostic Chart (Timer Diagnosis)

Courtesy of SUBARU OF AMERICA, INC.

• Abnormality Judgment 

  Judge as NG when the following conditions are established.

  JUDGMENT VALUE REFERENCE CHART
  
  

  Malfunction Criteria	Threshold Value
  losoaktimcpu - osoaktimic| / osoaktimcpu osoaktimcpu = Counter in ECM osoaktimic = Counter in soaking timer IC	> 0.4

• Normality Judgment 

  Judge as OK when the following conditions are established.

  JUDGMENT VALUE REFERENCE CHART
  
  

  Malfunction Criteria	Threshold Value
  |osoaktimcpu - osoaktimic| / osoaktimcpu	≤ 0.4