Fuel System Monitor

Fuel System Monitor
The monitor operates continuously throughout the trip. The monitor timing is every 128 msec.

The monitor compares the long-term adaptions for the current load site against a failure threshold. If the adaptions for that site are greater than the failure threshold the long-term failure counter is incremented. If this counter reaches a calibrated time the monitor then looks at the short term fuelling trim and compares this against another threshold and then the short term failure counter is incremented and if this counter reaches its failure threshold then a failure is flagged.

The normal counter operates when both long-term and short-term fuelling is within the thresholds. If the normal counter reaches its calibrated time then both failure counters are reset.

The diagram below shows the flagging of a rich failure on the A-bank of an engine: