Fail-Safe Function
WARNING: This page is about a different car, the 2011 Honda Pilot, 2010 Honda Pilot, and 2009 Honda Pilot. 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 PCM ignores that signal and substitute a pre-programmed value, that allows the engine to continue running. This causes a Confirmed DTC to be stored and the MIL to come on.