The factory CD gives a one paragraph description on FOM. I have some additional questions.

If a car goes into FOM, I assume that it can only be reset after the ignition is turned off and restarted and the computer goes through it self checks/tests?

If a car has a marginal/defective O2 sensor, would FOM only occur after the car reached operating temps since the O2 sensor has no effect unit the car is hot? Or does the computer rely on slight voltage from the heated sensor to check that it is functioning?

Tinker