Precautions For Removing Battery Terminal

WARNING: This page is about a different car, the 2016 Nissan Murano. However, it is still accessible from the selected car via links, so may be relevant.

When disconnecting the battery terminal, pay attention to the following:

Always use a 12V battery as power source.
Never disconnect battery terminal while engine is running.
When removing the 12V battery terminal, turn OFF the ignition switch and wait at least 30 seconds.
NOTE:
ECU may be active for several tens of seconds after the ignition switch is turned OFF. If the battery terminal is removed before ECU stops, then a DTC detection error or ECU data corruption may occur.

Fig 1: Disconnecting Negative Battery Terminal

Courtesy of NISSAN NORTH AMERICA, INC.

For vehicles with two batteries, be sure to connect the main battery and the sub-battery before turning ON the ignition switch.
NOTE: If the ignition switch is turned ON with any one of the terminals of main battery and sub-battery disconnected, then DTC may be detected.
After installing the 12V battery, always check "Self Diagnosis Result" of all ECUs and erase DTC.
NOTE:
The removal of 12V battery may cause a DTC detection error.