Possible Causes

WARNING: This page is about a different car, the 2003 Infiniti I35. However, it is still accessible from the selected car via links, so may be relevant.

Malfunction is detected when:

ECM calculation function is malfunctioning.
ECM EEPROM system is malfunctioning.
ECM self shut-off system is malfunctioning.

Only possible cause is a faulty ECM.