DTC Description: Notes
WARNING: This page is about a different car, the 2018 Nissan Titan XD. However, it is still accessible from the selected car via links, so may be relevant.
The Engine Control Module (ECM) receives constant voltage from the batteries through the unswitched battery wires that are connected directly to the positive (+) battery post. The ECM receives switched battery input through the ignition switch wire when the ignition switch is turned ON. At ignition switch OFF, the Engine Control Module (ECM) stays powered for a short period of time. During this time, the ECM will begin to save important data into memory. If the ECM is wired improperly, maintenance and DTC data could be corrupted or inaccurate.