Diagnostic Aids

When PCM is in backup fuel, fast idle and poor performance problems will exist. If DTC 18 is also stored, a problem with the 5-volt reference circuit or the sensor ground circuit may exist. If air is present in the fuel system DTC 17 may set.

Fig 1: DTC 17 Schematic ("G" & "P" Series) High Resolution Circuit Fault

Fig 2: DTC 17 Flow Chart ("G" & "P" Series) High Resolution Circuit Fault