Fail-safe Function
WARNING: This page is about a different car, the 2010 Acura TL and 2009 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.
When an abnormality occurs in the signal from a sensor or from another control unit, the ECM/PCM ignores that signal and substitutes a pre-programmed value for them that allows the engine to continue running. This causes a Confirmed DTC to be stored and the MIL to come on.