Nissan Repair: Nissan Pintara ECM, nissan pintara, mixture ratio

Question
If the ECM for the 1991 Pintara has to be in mode 3 for diagnostic fault codes, what do the other modes mean?

Answer
Hi Ric, mode 1: mixture ratio feedback control monitor A. Mode 2: mixture ratio feedback control monitor B. Mode 3: Self Diagnosis. Mode 4: switches on/of diagnosis. Mode 5: real time diagnosis.  Let me know for detailed explanation of the mode that interests you, but mode 3 is the one commonly used.