Technical ECU error code reset itself?

[silex]

My engine light went out after being on for 3 days, it has been another 3 days without it coming back on, am I safe to assume it was just an intermittant problem,?
It's just that a Fiat garage told me that the ECU will just reset itself after a few days and clear any fault lights, as a default action and there is still likely to be a fault.
This sounds odd to me. does this sound right?

 

[D4nny8oy]

A fault has to be present for three consecutive cycles before the lamp will illuminate, unless it's a serious problem. If it's an intermittant problem, and doesn't re-occur in the next three cycles, the lamp will go out although the error will still be recorded and when it last occured.

Just because the lamp has gone out for now, doesn't mean the issue won't occur again.

 

[silex]

Many thanks, I assume then, that if the light is not on there is no problem, if the fault does recurr, the light will come on